diff --git a/Frameworks/vgmstream/vgmstream.xcodeproj/project.pbxproj b/Frameworks/vgmstream/vgmstream.xcodeproj/project.pbxproj
index 26406498a..47671b387 100644
--- a/Frameworks/vgmstream/vgmstream.xcodeproj/project.pbxproj
+++ b/Frameworks/vgmstream/vgmstream.xcodeproj/project.pbxproj
@@ -343,6 +343,10 @@
 		83709E0A1ECBC1A4005C03D3 /* waa_wac_wad_wam.c in Sources */ = {isa = PBXBuildFile; fileRef = 83709E041ECBC1A4005C03D3 /* waa_wac_wad_wam.c */; };
 		83709E0D1ECBC1C3005C03D3 /* mc3_decoder.c in Sources */ = {isa = PBXBuildFile; fileRef = 83709E0B1ECBC1C3005C03D3 /* mc3_decoder.c */; };
 		83709E0E1ECBC1C3005C03D3 /* psv_decoder.c in Sources */ = {isa = PBXBuildFile; fileRef = 83709E0C1ECBC1C3005C03D3 /* psv_decoder.c */; };
+		8374EE3E1F787AB600033E90 /* ffmpeg_decoder_utils_ea_xma.c in Sources */ = {isa = PBXBuildFile; fileRef = 8374EE361F787AB500033E90 /* ffmpeg_decoder_utils_ea_xma.c */; };
+		8374EE3F1F787AB600033E90 /* ffmpeg_decoder_utils_wwise_opus.c in Sources */ = {isa = PBXBuildFile; fileRef = 8374EE3B1F787AB600033E90 /* ffmpeg_decoder_utils_wwise_opus.c */; };
+		8374EE401F787AB600033E90 /* ffmpeg_decoder_utils.h in Headers */ = {isa = PBXBuildFile; fileRef = 8374EE3C1F787AB600033E90 /* ffmpeg_decoder_utils.h */; };
+		8374EE411F787AB600033E90 /* ffmpeg_decoder_utils.c in Sources */ = {isa = PBXBuildFile; fileRef = 8374EE3D1F787AB600033E90 /* ffmpeg_decoder_utils.c */; };
 		838BDB641D3AF08C0022CA6F /* libavcodec.a in Frameworks */ = {isa = PBXBuildFile; fileRef = 838BDB611D3AF08C0022CA6F /* libavcodec.a */; };
 		838BDB651D3AF08C0022CA6F /* libavformat.a in Frameworks */ = {isa = PBXBuildFile; fileRef = 838BDB621D3AF08C0022CA6F /* libavformat.a */; };
 		838BDB661D3AF08C0022CA6F /* libavutil.a in Frameworks */ = {isa = PBXBuildFile; fileRef = 838BDB631D3AF08C0022CA6F /* libavutil.a */; };
@@ -845,6 +849,10 @@
 		83709E041ECBC1A4005C03D3 /* waa_wac_wad_wam.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = waa_wac_wad_wam.c; sourceTree = "<group>"; };
 		83709E0B1ECBC1C3005C03D3 /* mc3_decoder.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = mc3_decoder.c; sourceTree = "<group>"; };
 		83709E0C1ECBC1C3005C03D3 /* psv_decoder.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = psv_decoder.c; sourceTree = "<group>"; };
+		8374EE361F787AB500033E90 /* ffmpeg_decoder_utils_ea_xma.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = ffmpeg_decoder_utils_ea_xma.c; sourceTree = "<group>"; };
+		8374EE3B1F787AB600033E90 /* ffmpeg_decoder_utils_wwise_opus.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = ffmpeg_decoder_utils_wwise_opus.c; sourceTree = "<group>"; };
+		8374EE3C1F787AB600033E90 /* ffmpeg_decoder_utils.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ffmpeg_decoder_utils.h; sourceTree = "<group>"; };
+		8374EE3D1F787AB600033E90 /* ffmpeg_decoder_utils.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = ffmpeg_decoder_utils.c; sourceTree = "<group>"; };
 		838BDB611D3AF08C0022CA6F /* libavcodec.a */ = {isa = PBXFileReference; lastKnownFileType = archive.ar; name = libavcodec.a; path = ../../ThirdParty/ffmpeg/lib/libavcodec.a; sourceTree = "<group>"; };
 		838BDB621D3AF08C0022CA6F /* libavformat.a */ = {isa = PBXFileReference; lastKnownFileType = archive.ar; name = libavformat.a; path = ../../ThirdParty/ffmpeg/lib/libavformat.a; sourceTree = "<group>"; };
 		838BDB631D3AF08C0022CA6F /* libavutil.a */ = {isa = PBXFileReference; lastKnownFileType = archive.ar; name = libavutil.a; path = ../../ThirdParty/ffmpeg/lib/libavutil.a; sourceTree = "<group>"; };
@@ -1042,6 +1050,10 @@
 		836F6DDF18BDC2180095E648 /* coding */ = {
 			isa = PBXGroup;
 			children = (
+				8374EE361F787AB500033E90 /* ffmpeg_decoder_utils_ea_xma.c */,
+				8374EE3B1F787AB600033E90 /* ffmpeg_decoder_utils_wwise_opus.c */,
+				8374EE3D1F787AB600033E90 /* ffmpeg_decoder_utils.c */,
+				8374EE3C1F787AB600033E90 /* ffmpeg_decoder_utils.h */,
 				83AA5D0E1F6E2F5F0020821C /* ea_xa_decoder.c */,
 				83AA5D151F6E2F600020821C /* ea_xas_decoder.c */,
 				83AA5D141F6E2F600020821C /* mpeg_custom_utils_awc.c */,
@@ -1460,6 +1472,7 @@
 				836F6F2718BDC2190095E648 /* g72x_state.h in Headers */,
 				839E21E01F2EDAF100EE54D7 /* vorbis_custom_data_fsb.h in Headers */,
 				836F705418BDC2190095E648 /* streamfile.h in Headers */,
+				8374EE401F787AB600033E90 /* ffmpeg_decoder_utils.h in Headers */,
 				83A3F0761E3AD8B900D6A794 /* stack_alloc.h in Headers */,
 				83A3F0751E3AD8B900D6A794 /* formats.h in Headers */,
 				8323894B1D22419B00482226 /* clHCA.h in Headers */,
@@ -1668,6 +1681,7 @@
 				836F6F7018BDC2190095E648 /* apple_caff.c in Sources */,
 				836F700018BDC2190095E648 /* ps2_svag.c in Sources */,
 				836F6FB618BDC2190095E648 /* ngc_sck_dsp.c in Sources */,
+				8374EE3F1F787AB600033E90 /* ffmpeg_decoder_utils_wwise_opus.c in Sources */,
 				836F6F2818BDC2190095E648 /* ima_decoder.c in Sources */,
 				836F702318BDC2190095E648 /* rsf.c in Sources */,
 				83299FD01E7660C7003A3242 /* bik.c in Sources */,
@@ -1711,6 +1725,7 @@
 				83709E0D1ECBC1C3005C03D3 /* mc3_decoder.c in Sources */,
 				836F6FA818BDC2190095E648 /* nds_swav.c in Sources */,
 				836F6F3F18BDC2190095E648 /* ast_blocked.c in Sources */,
+				8374EE411F787AB600033E90 /* ffmpeg_decoder_utils.c in Sources */,
 				833A7A2E1ED11961003EC53E /* xau.c in Sources */,
 				836F6F5018BDC2190095E648 /* mxch_blocked.c in Sources */,
 				836F6FB518BDC2190095E648 /* ngc_pdt.c in Sources */,
@@ -1868,6 +1883,7 @@
 				831BA61C1EAC61A500CF89B0 /* sxd.c in Sources */,
 				836F6F8018BDC2190095E648 /* dsp_bdsp.c in Sources */,
 				836F6F9618BDC2190095E648 /* lsf.c in Sources */,
+				8374EE3E1F787AB600033E90 /* ffmpeg_decoder_utils_ea_xma.c in Sources */,
 				836F6FC818BDC2190095E648 /* pos.c in Sources */,
 				8350C05A1E071990009E0A93 /* ps2_svag_snk.c in Sources */,
 				836F6F8918BDC2190095E648 /* gca.c in Sources */,
diff --git a/Frameworks/vgmstream/vgmstream/src/coding/coding.h b/Frameworks/vgmstream/vgmstream/src/coding/coding.h
index 3ec4efcaf..0c21a18d5 100644
--- a/Frameworks/vgmstream/vgmstream/src/coding/coding.h
+++ b/Frameworks/vgmstream/vgmstream/src/coding/coding.h
@@ -202,9 +202,8 @@ void free_at3plus(maiatrac3plus_codec_data *data);
 #ifdef VGM_USE_FFMPEG
 /* ffmpeg_decoder */
 ffmpeg_codec_data * init_ffmpeg_offset(STREAMFILE *streamFile, uint64_t start, uint64_t size);
-ffmpeg_codec_data * init_ffmpeg_offset_index(STREAMFILE *streamFile, uint64_t start, uint64_t size, int stream_index);
 ffmpeg_codec_data * init_ffmpeg_header_offset(STREAMFILE *streamFile, uint8_t * header, uint64_t header_size, uint64_t start, uint64_t size);
-ffmpeg_codec_data * init_ffmpeg_header_offset_index(STREAMFILE *streamFile, uint8_t * header, uint64_t header_size, uint64_t start, uint64_t size, int stream_index);
+ffmpeg_codec_data * init_ffmpeg_config(STREAMFILE *streamFile, uint8_t * header, uint64_t header_size, uint64_t start, uint64_t size, ffmpeg_custom_config * config);
 
 void decode_ffmpeg(VGMSTREAM *stream, sample * outbuf, int32_t samples_to_do, int channels);
 void reset_ffmpeg(VGMSTREAM *vgmstream);
@@ -212,6 +211,10 @@ void seek_ffmpeg(VGMSTREAM *vgmstream, int32_t num_sample);
 void free_ffmpeg(ffmpeg_codec_data *data);
 
 void ffmpeg_set_skip_samples(ffmpeg_codec_data * data, int skip_samples);
+
+
+size_t ffmpeg_make_opus_header(uint8_t * buf, int buf_size, int channels, int skip, int sample_rate);
+size_t ffmpeg_get_eaxma_virtual_size(off_t real_offset, size_t real_size, STREAMFILE *streamFile);
 #endif
 
 /* coding_utils */
@@ -256,5 +259,4 @@ void xma2_parse_xma2_chunk(STREAMFILE *streamFile, off_t chunk_offset, int * cha
 size_t atrac3_bytes_to_samples(size_t bytes, int full_block_align);
 size_t atrac3plus_bytes_to_samples(size_t bytes, int full_block_align);
 
-
 #endif /*_CODING_H*/
diff --git a/Frameworks/vgmstream/vgmstream/src/coding/ffmpeg_decoder.c b/Frameworks/vgmstream/vgmstream/src/coding/ffmpeg_decoder.c
index ae31a4bef..1dc445505 100644
--- a/Frameworks/vgmstream/vgmstream/src/coding/ffmpeg_decoder.c
+++ b/Frameworks/vgmstream/vgmstream/src/coding/ffmpeg_decoder.c
@@ -1,4 +1,5 @@
 #include "coding.h"
+#include "ffmpeg_decoder_utils.h"
 
 #ifdef VGM_USE_FFMPEG
 
@@ -181,51 +182,53 @@ fail:
 /* AVIO CALLBACKS                               */
 /* ******************************************** */
 
-/* AVIO callback: read stream, skipping external headers if needed */
+/* AVIO callback: read stream, handling custom data */
 static int ffmpeg_read(void *opaque, uint8_t *buf, int buf_size) {
     ffmpeg_codec_data *data = (ffmpeg_codec_data *) opaque;
-    uint64_t offset = data->offset;
+    int ret = 0;
     int max_to_copy = 0;
-    int ret;
 
-    if (data->header_insert_block) {
-        if (offset < data->header_size) {
-            max_to_copy = (int)(data->header_size - offset);
+    //;VGM_LOG("AVIO read: r_off=%"PRIx64", v_off=%"PRIx64", b_size=%x\n", data->real_offset, data->virtual_offset, buf_size);fflush(stdout);
+
+    /* clamp reads */
+    if (data->virtual_offset + buf_size > data->virtual_size)
+        buf_size = data->virtual_size - data->virtual_offset;
+    if (buf_size == 0)
+        return ret;
+
+    /* handle reads on inserted header */
+    if (data->header_size) {
+        if (data->virtual_offset < data->header_size) {
+            max_to_copy = (int)(data->header_size - data->virtual_offset);
             if (max_to_copy > buf_size) {
                 max_to_copy = buf_size;
             }
-            memcpy(buf, data->header_insert_block + offset, max_to_copy);
+
+            //;VGM_LOG("AVIO header: v_off=%lx, h_size=%lx, mtc=%x, b_size=%x\n",  (off_t)data->virtual_offset, (off_t)data->header_size, max_to_copy, buf_size);fflush(stdout);
+            memcpy(buf, data->header_insert_block + data->virtual_offset, max_to_copy);
             buf += max_to_copy;
             buf_size -= max_to_copy;
-            offset += max_to_copy;
-            if (!buf_size) {
-                data->offset = offset;
-                return max_to_copy;
+            data->virtual_offset += max_to_copy; /* adjust for reads below */
+
+            if (buf_size == 0) {
+                return max_to_copy; /* offset still in header */
             }
         }
-        offset -= data->header_size;
     }
 
-    /* when "fake" size is smaller than "real" size we need to make sure bytes_read (ret) is clamped;
-     * it confuses FFmpeg in rare cases (STREAMFILE may have valid data after size) */
-    if (offset + buf_size > data->size + data->header_size) {
-        buf_size = data->size - offset; /* header "read" is manually inserted later */
+    /* main read */
+    switch(data->config.type) {
+        case FFMPEG_EA_XMA:     ret = ffmpeg_custom_read_eaxma(data, buf, buf_size); break;
+        case FFMPEG_WWISE_OPUS: ret = ffmpeg_custom_read_wwise_opus(data, buf, buf_size); break;
+      //case FFMPEG_EA_SCHL:    ret = ffmpeg_custom_read_ea_schl(data, buf, buf_size); break;
+      //case FFMPEG_SFH:        ret = ffmpeg_custom_read_sfh(data, buf, buf_size); break;
+        default:                ret = ffmpeg_custom_read_standard(data, buf, buf_size); break;
     }
+    data->virtual_offset += ret;
+    //data->real_offset = ; /* must be updated in function */
 
-    ret = read_streamfile(buf, offset + data->start, buf_size, data->streamfile);
-    if (ret > 0) {
-        offset += ret;
-        if (data->header_insert_block) {
-            ret += max_to_copy;
-        }
-    }
-
-    if (data->header_insert_block) {
-        offset += data->header_size;
-    }
-
-    data->offset = offset;
-    return ret;
+    //;VGM_LOG("AVIO read done: ret=%x, r_off=%"PRIx64", v_off=%"PRIx64"\n", ret + max_to_copy, data->real_offset, data->virtual_offset);fflush(stdout);
+    return ret + max_to_copy;
 }
 
 /* AVIO callback: write stream not needed */
@@ -233,53 +236,92 @@ static int ffmpeg_write(void *opaque, uint8_t *buf, int buf_size) {
     return -1;
 }
 
-/* AVIO callback: seek stream, skipping external headers if needed */
+/* AVIO callback: seek stream, handling custom data */
 static int64_t ffmpeg_seek(void *opaque, int64_t offset, int whence) {
     ffmpeg_codec_data *data = (ffmpeg_codec_data *) opaque;
     int ret = 0;
 
+    /* get cache'd size */
     if (whence & AVSEEK_SIZE) {
-        return data->size + data->header_size;
+        //;VGM_LOG("AVIO size: v_size=%"PRIx64", h_size=%"PRIx64", r_size=%"PRIx64", r_start=%"PRIx64"\n", data->virtual_size, data->header_size, data->real_size, data->real_start);fflush(stdout);
+        return data->virtual_size;
     }
+
+    //;VGM_LOG("AVIO seek: off=%"PRIx64" r_off=%"PRIx64", v_off=%"PRIx64"\n", offset, data->real_offset, data->virtual_offset);fflush(stdout);
+
     whence &= ~(AVSEEK_SIZE | AVSEEK_FORCE);
-    /* false offsets, on reads data->start will be added */
+
+    /* find the final offset FFmpeg sees (within fake header + virtual size) */
     switch (whence) {
-        case SEEK_SET:
+        case SEEK_SET: /* absolute */
             break;
 
-        case SEEK_CUR:
-            offset += data->offset;
+        case SEEK_CUR: /* relative to current */
+            offset += data->virtual_offset;
             break;
 
-        case SEEK_END:
-            offset += data->size;
-            if (data->header_insert_block)
-                offset += data->header_size;
+        case SEEK_END: /* relative to file end (should be negative) */
+            offset += data->virtual_size;
             break;
     }
 
-    /* clamp offset; fseek returns 0 when offset > size, too */
-    if (offset > data->size + data->header_size) {
-        offset = data->size + data->header_size;
+    /* clamp offset; fseek does this too */
+    if (offset > data->virtual_size)
+        offset = data->virtual_size;
+    else if (offset < 0)
+        offset = 0;
+
+    /* no change */
+    if (data->virtual_offset == offset) {
+        return ret;
     }
 
-    data->offset = offset;
+    /* seeks inside fake header */
+    if (offset < data->header_size) {
+        data->virtual_offset = offset;
+        data->real_offset = data->real_start;
+        return ret;
+    }
+
+    /* main seek */
+    switch(data->config.type) {
+        case FFMPEG_EA_XMA:     offset = ffmpeg_custom_seek_eaxma(data, offset); break;
+        case FFMPEG_WWISE_OPUS: offset = ffmpeg_custom_seek_wwise_opus(data, offset); break;
+      //case FFMPEG_EA_SCHL:    offset = ffmpeg_custom_seek_ea_schl(data, offset); break;
+      //case FFMPEG_SFH:        offset = ffmpeg_custom_seek_sfh(data, offset); break;
+        default:                offset = ffmpeg_custom_seek_standard(data, offset); break;
+    }
+    data->virtual_offset = offset;
+    //data->real_offset = ; /* must be updated in function */
+
+    //;VGM_LOG("AVIO seek done: r_off=%"PRIx64", v_off=%"PRIx64"\n", data->real_offset, data->virtual_offset);fflush(stdout);
     return ret;
 }
 
+/* called on init, not a callback */ //todo rename to ffmpeg_init
+static int64_t ffmpeg_size(ffmpeg_codec_data * data) {
+    int64_t bytes;
+    switch(data->config.type) {
+        case FFMPEG_EA_XMA:     bytes = ffmpeg_custom_size_eaxma(data); break;
+        case FFMPEG_WWISE_OPUS: bytes = ffmpeg_custom_size_wwise_opus(data); break;
+      //case FFMPEG_EA_SCHL:    bytes = ffmpeg_custom_size_ea_schl(data); break;
+      //case FFMPEG_SFH:        bytes = ffmpeg_custom_size_sfh(data); break;
+        default:                bytes = ffmpeg_custom_size_standard(data); break;
+    }
+
+    return bytes;
+}
+
 
 /* ******************************************** */
 /* MAIN INIT/DECODER                            */
 /* ******************************************** */
 
 ffmpeg_codec_data * init_ffmpeg_offset(STREAMFILE *streamFile, uint64_t start, uint64_t size) {
-    return init_ffmpeg_header_offset_index(streamFile, NULL,0, start,size, 0);
-}
-ffmpeg_codec_data * init_ffmpeg_offset_index(STREAMFILE *streamFile, uint64_t start, uint64_t size, int stream_index) {
-    return init_ffmpeg_header_offset_index(streamFile, NULL,0, start,size, stream_index);
+    return init_ffmpeg_config(streamFile, NULL,0, start,size, NULL);
 }
 ffmpeg_codec_data * init_ffmpeg_header_offset(STREAMFILE *streamFile, uint8_t * header, uint64_t header_size, uint64_t start, uint64_t size) {
-    return init_ffmpeg_header_offset_index(streamFile, header,header_size, start,size, 0);
+    return init_ffmpeg_config(streamFile, header,header_size, start,size, NULL);
 }
 
 
@@ -292,7 +334,7 @@ ffmpeg_codec_data * init_ffmpeg_header_offset(STREAMFILE *streamFile, uint8_t *
  * NULL header can used given if the stream has internal data recognized by FFmpeg at offset.
  * Stream index can be passed to FFmpeg, if the format has multiple streams (1=first).
  */
-ffmpeg_codec_data * init_ffmpeg_header_offset_index(STREAMFILE *streamFile, uint8_t * header, uint64_t header_size, uint64_t start, uint64_t size, int stream_index) {
+ffmpeg_codec_data * init_ffmpeg_config(STREAMFILE *streamFile, uint8_t * header, uint64_t header_size, uint64_t start, uint64_t size, ffmpeg_custom_config * config) {
     char filename[PATH_LIMIT];
     ffmpeg_codec_data * data;
     int errcode, i;
@@ -315,17 +357,25 @@ ffmpeg_codec_data * init_ffmpeg_header_offset_index(STREAMFILE *streamFile, uint
     data->streamfile = streamFile->open(streamFile, filename, STREAMFILE_DEFAULT_BUFFER_SIZE);
     if (!data->streamfile) goto fail;
 
-    data->start = start;
-    data->size = size;
+    if (config) {
+        memcpy(&data->config, config, sizeof(ffmpeg_custom_config));
+    }
 
-
-    /* insert fake header to trick FFmpeg into demuxing/decoding the stream */
+    /* fake header to trick FFmpeg into demuxing/decoding the stream */
     if (header_size > 0) {
         data->header_size = header_size;
         data->header_insert_block = av_memdup(header, header_size);
         if (!data->header_insert_block) goto fail;
     }
 
+    data->real_start = start;
+    data->real_offset = data->real_start;
+    data->real_size = size;
+    data->virtual_offset = 0;
+    data->virtual_size = ffmpeg_size(data);
+    data->virtual_base = 0;
+    if (data->virtual_size == 0) goto fail;
+
     /* setup IO, attempt to autodetect format and gather some info */
     data->buffer = av_malloc(FFMPEG_DEFAULT_IO_BUFFER_SIZE);
     if (!data->buffer) goto fail;
@@ -354,7 +404,7 @@ ffmpeg_codec_data * init_ffmpeg_header_offset_index(STREAMFILE *streamFile, uint
             streamCount++;
 
             /* select Nth audio stream if specified, or first one */
-            if (streamIndex < 0 || (stream_index > 0 && streamCount == stream_index)) {
+            if (streamIndex < 0 || (data->config.stream_index > 0 && streamCount == data->config.stream_index)) {
                 codecPar = stream->codecpar;
                 streamIndex = i;
             }
@@ -363,7 +413,7 @@ ffmpeg_codec_data * init_ffmpeg_header_offset_index(STREAMFILE *streamFile, uint
         if (i != streamIndex)
             stream->discard = AVDISCARD_ALL; /* disable demuxing for other streams */
     }
-    if (streamCount < stream_index) goto fail;
+    if (streamCount < data->config.stream_index) goto fail;
     if (streamIndex < 0 || !codecPar) goto fail;
 
     data->streamIndex = streamIndex;
diff --git a/Frameworks/vgmstream/vgmstream/src/coding/ffmpeg_decoder_utils.c b/Frameworks/vgmstream/vgmstream/src/coding/ffmpeg_decoder_utils.c
new file mode 100644
index 000000000..2d674d87b
--- /dev/null
+++ b/Frameworks/vgmstream/vgmstream/src/coding/ffmpeg_decoder_utils.c
@@ -0,0 +1,28 @@
+#include "coding.h"
+#include "ffmpeg_decoder_utils.h"
+
+#ifdef VGM_USE_FFMPEG
+
+/**
+ * Standard read mode: virtual values are 1:1 but inside a portion of the streamfile (between real_start and real_size).
+ */
+
+
+int ffmpeg_custom_read_standard(ffmpeg_codec_data *data, uint8_t *buf, int buf_size) {
+    size_t bytes = read_streamfile(buf, data->real_offset, buf_size, data->streamfile);
+    data->real_offset += bytes;
+
+    return bytes;
+}
+
+int64_t ffmpeg_custom_seek_standard(ffmpeg_codec_data *data, int64_t virtual_offset) {
+    data->real_offset = data->real_start + (virtual_offset - data->header_size);
+    return virtual_offset;
+}
+
+int64_t ffmpeg_custom_size_standard(ffmpeg_codec_data *data) {
+    return data->real_size + data->header_size;
+}
+
+
+#endif
diff --git a/Frameworks/vgmstream/vgmstream/src/coding/ffmpeg_decoder_utils.h b/Frameworks/vgmstream/vgmstream/src/coding/ffmpeg_decoder_utils.h
new file mode 100644
index 000000000..18957e3c3
--- /dev/null
+++ b/Frameworks/vgmstream/vgmstream/src/coding/ffmpeg_decoder_utils.h
@@ -0,0 +1,44 @@
+#ifndef _FFMPEG_DECODER_UTILS_
+#define _FFMPEG_DECODER_UTILS_
+
+#ifdef VGM_USE_FFMPEG
+/* used by ffmpeg_decoder.c, but scattered in other .c files */
+
+/**
+ * Custom read/seek for data transformation. Must handle seeks+reads from virtual offsets, ie.-
+ * reads "real/file" data, not decodable by FFmpeg, and transforms to decodable "virtual/buffer" data,
+ * block by block (must seek to closest file offset and adjust on reads).
+ *
+ * To simplify, functions won't be called in common cases (seek over filesize, no change in offset, etc),
+ * and fake header seeks/reads are handled externally. Real offset must be updated internally though.
+ *
+ * example (a 0x100 block transforms to a 0x150 block):
+ * - seek 0: file-offset=0, virtual-offset=0
+ * - read 0x150: file-read=0x100 transforms to buffer=0x150
+ * - new file-offset=0x100, virtual-offset=0x150
+ * - seek 0x310: file-offset=0x200, virtual-offset=0x310 (closest virtual block is 0x150+0x150, + 0x10 adjusted on reads)
+ */
+
+int ffmpeg_custom_read_standard(ffmpeg_codec_data *data, uint8_t *buf, int buf_size);
+int64_t ffmpeg_custom_seek_standard(ffmpeg_codec_data *data, int64_t virtual_offset);
+int64_t ffmpeg_custom_size_standard(ffmpeg_codec_data *data);
+
+int ffmpeg_custom_read_eaxma(ffmpeg_codec_data *data, uint8_t *buf, int buf_size);
+int64_t ffmpeg_custom_seek_eaxma(ffmpeg_codec_data *data, int64_t virtual_offset);
+int64_t ffmpeg_custom_size_eaxma(ffmpeg_codec_data *data);
+
+int ffmpeg_custom_read_wwise_opus(ffmpeg_codec_data *data, uint8_t *buf, int buf_size);
+int64_t ffmpeg_custom_seek_wwise_opus(ffmpeg_codec_data *data, int64_t virtual_offset);
+int64_t ffmpeg_custom_size_wwise_opus(ffmpeg_codec_data *data);
+
+//int ffmpeg_custom_read_ea_schl(ffmpeg_codec_data *data, uint8_t *buf, int buf_size);
+//int64_t ffmpeg_custom_seek_ea_schl(ffmpeg_codec_data *data, int64_t virtual_offset);
+//int64_t ffmpeg_custom_size_ea_schl(ffmpeg_codec_data *data);
+
+//int ffmpeg_custom_read_sfh(ffmpeg_codec_data *data, uint8_t *buf, int buf_size);
+//int64_t ffmpeg_custom_seek_sfh(ffmpeg_codec_data *data, int64_t virtual_offset);
+//int64_t ffmpeg_custom_size_sfh(ffmpeg_codec_data *data);
+
+#endif
+
+#endif/*_FFMPEG_DECODER_UTILS_*/
diff --git a/Frameworks/vgmstream/vgmstream/src/coding/ffmpeg_decoder_utils_ea_xma.c b/Frameworks/vgmstream/vgmstream/src/coding/ffmpeg_decoder_utils_ea_xma.c
new file mode 100644
index 000000000..84e69fd73
--- /dev/null
+++ b/Frameworks/vgmstream/vgmstream/src/coding/ffmpeg_decoder_utils_ea_xma.c
@@ -0,0 +1,153 @@
+#include "coding.h"
+#include "ffmpeg_decoder_utils.h"
+
+#ifdef VGM_USE_FFMPEG
+
+#define EAXMA_XMA_BLOCK_SIZE 0x800
+
+/**
+ * EA-XMA is XMA with padding removed (so a real 0x450 block would be padded to a virtual 0x800 block).
+ * //todo missing multichannel (packet multistream) support, unknown layout
+ */
+
+
+int ffmpeg_custom_read_eaxma(ffmpeg_codec_data *data, uint8_t *buf, int buf_size) {
+    uint8_t v_buf[0x8000]; /* intermediate buffer, could be simplified */
+    int buf_done = 0;
+    uint64_t real_offset = data->real_offset;
+    uint64_t virtual_offset = data->virtual_offset - data->header_size;
+    uint64_t virtual_base = data->virtual_base;
+
+
+    /* read and transform SNS/EA-XMA block into XMA block by adding padding */
+    while (buf_done < buf_size) {
+        int bytes_to_copy;
+        size_t data_size, extra_size = 0, gap_size = 0;
+        size_t block_size = read_32bitBE(real_offset, data->streamfile);
+        /* 0x04(4): some kind of size? 0x08(4): decoded samples */
+
+        /* setup */
+        data_size = (block_size & 0x00FFFFFF) - 0x0c; //todo last block size may be slightly off?
+        if (data_size % EAXMA_XMA_BLOCK_SIZE) /* aligned padding */
+            extra_size = EAXMA_XMA_BLOCK_SIZE - (data_size % EAXMA_XMA_BLOCK_SIZE);
+        if (buf_done == 0) /* first read */
+            gap_size = virtual_offset - virtual_base; /* might start a few bytes into the block */
+
+        if (data_size + extra_size > 0x8000) {
+            VGM_LOG("EA-XMA: total size bigger than buffer at %lx\n", (off_t)real_offset);
+            return 0;
+        }
+
+        bytes_to_copy = data_size + extra_size - gap_size;
+        if (bytes_to_copy > buf_size - buf_done)
+            bytes_to_copy = buf_size - buf_done;
+
+        /* transform */
+        read_streamfile(v_buf, real_offset + 0x0c, data_size, data->streamfile);
+        memset(v_buf + data_size, 0xFF, extra_size); /* padding can be any value, typically 0xFF */
+        memcpy(buf + buf_done, v_buf + gap_size, bytes_to_copy);
+
+        /* move when block is fully done */
+        if (data_size + extra_size == bytes_to_copy + gap_size) {
+            real_offset += (block_size & 0x00FFFFFF);
+            virtual_base += data_size + extra_size;
+        }
+
+        buf_done += bytes_to_copy;
+
+        /* exit on last block just in case, though should reach file size */
+        if (block_size & 0x80000000)
+            break;
+    }
+
+
+    data->real_offset = real_offset;
+    data->virtual_base = virtual_base;
+    return buf_size;
+}
+
+int64_t ffmpeg_custom_seek_eaxma(ffmpeg_codec_data *data, int64_t virtual_offset) {
+    int64_t real_offset, virtual_base;
+    int64_t current_virtual_offset = data->virtual_offset;
+
+    /* Find SNS block start closest to offset. ie. virtual_offset 0x1A10 could mean SNS blocks
+     * of 0x456+0x820 padded to 0x800+0x1000 (base) + 0x210 (extra for reads), thus real_offset = 0xC76 */
+
+    if (virtual_offset > current_virtual_offset) { /* seek after current: start from current block */
+        real_offset = data->real_offset;
+        virtual_base = data->virtual_base;
+    }
+    else { /* seek before current: start from the beginning */
+        real_offset = data->real_start;
+        virtual_base = 0;
+    }
+
+
+    /* find target block */
+    while (virtual_base < virtual_offset) {
+        size_t data_size, extra_size = 0;
+        size_t block_size = read_32bitBE(real_offset, data->streamfile);
+
+        data_size = (block_size & 0x00FFFFFF) - 0x0c;
+        if (data_size % EAXMA_XMA_BLOCK_SIZE)
+            extra_size = EAXMA_XMA_BLOCK_SIZE - (data_size % EAXMA_XMA_BLOCK_SIZE);
+
+        /* stop if virtual_offset lands inside current block */
+        if (data_size + extra_size > virtual_offset)
+            break;
+
+        real_offset += (block_size & 0x00FFFFFF);
+        virtual_base += data_size + extra_size;
+    }
+
+    /* closest we can use for reads */
+    data->real_offset = real_offset;
+    data->virtual_base = virtual_base;
+
+    return virtual_offset;
+}
+
+int64_t ffmpeg_custom_size_eaxma(ffmpeg_codec_data *data) {
+
+    uint64_t virtual_size = data->config.virtual_size;
+    if (!virtual_size)
+        return 0;
+
+    return virtual_size + data->header_size;
+}
+
+/* needed to know in meta for fake RIFF */
+size_t ffmpeg_get_eaxma_virtual_size(off_t real_offset, size_t real_size, STREAMFILE *streamFile) {
+    size_t virtual_size = 0;
+
+    /* count all SNS/EAXMA blocks size + padding size */
+    while (real_offset < real_size) {
+        size_t data_size;
+        size_t block_size = read_32bitBE(real_offset, streamFile);
+
+        data_size = (block_size & 0x00FFFFFF) - 0x0c;
+
+        if ((block_size & 0xFF000000) && !(block_size & 0x80000000)) {
+            VGM_LOG("EA-XMA: unknown flag found at %lx\n", (off_t)real_offset);
+            goto fail;
+        }
+
+        real_offset += (block_size & 0x00FFFFFF);
+
+        virtual_size += data_size;
+        if (data_size % EAXMA_XMA_BLOCK_SIZE) /* XMA block padding */
+            virtual_size += EAXMA_XMA_BLOCK_SIZE - (data_size % EAXMA_XMA_BLOCK_SIZE);
+
+        /* exit on last block just in case, though should reach real_size */
+        if (block_size & 0x80000000)
+            break;
+    }
+
+    return virtual_size;
+
+fail:
+    return 0;
+
+}
+
+#endif
diff --git a/Frameworks/vgmstream/vgmstream/src/coding/ffmpeg_decoder_utils_wwise_opus.c b/Frameworks/vgmstream/vgmstream/src/coding/ffmpeg_decoder_utils_wwise_opus.c
new file mode 100644
index 000000000..377701328
--- /dev/null
+++ b/Frameworks/vgmstream/vgmstream/src/coding/ffmpeg_decoder_utils_wwise_opus.c
@@ -0,0 +1,346 @@
+#include "coding.h"
+#include "ffmpeg_decoder_utils.h"
+#include <string.h>
+
+#ifdef VGM_USE_FFMPEG
+
+
+/**
+ * Xiph Opus without Ogg layer and custom packet headers. This creates valid Ogg pages with single Opus packets.
+ * Wwise opus looks encoded roughly like "opusenc --hard-cbr --framesize 40". The packets are Opus-compliant.
+ *
+ * Info, CRC and stuff:
+ *   https://www.opus-codec.org/docs/
+ *   https://tools.ietf.org/html/rfc7845.html
+ *   https://github.com/hcs64/ww2ogg
+ */
+
+static size_t make_oggs_page(uint8_t * buf, int buf_size, size_t data_size, int page_sequence, int granule);
+static size_t make_opus_header(uint8_t * buf, int buf_size, int channels, int skip, int sample_rate);
+static size_t make_opus_comment(uint8_t * buf, int buf_size);
+static uint32_t get_opus_samples_per_frame(const uint8_t * data, int Fs);
+
+
+size_t ffmpeg_make_opus_header(uint8_t * buf, int buf_size, int channels, int skip, int sample_rate) {
+    int buf_done = 0;
+    size_t bytes;
+
+    if (buf_size < 0x100) /* approx */
+        goto fail;
+
+    /* make header */
+    bytes = make_opus_header(buf+buf_done + 0x1c,buf_size, channels, skip, sample_rate);
+    make_oggs_page(buf+buf_done + 0x00,buf_size, bytes, 0, 0);
+    buf_done += 0x1c + bytes;
+
+    /* make comment */
+    bytes = make_opus_comment(buf+buf_done + 0x1c,buf_size);
+    make_oggs_page(buf+buf_done + 0x00,buf_size, bytes, 1, 0);
+    buf_done += 0x1c + bytes;
+
+    return buf_done;
+fail:
+    return 0;
+}
+
+
+int ffmpeg_custom_read_wwise_opus(ffmpeg_codec_data *data, uint8_t *buf, int buf_size) {
+    uint8_t v_buf[0x8000]; /* intermediate buffer, could be simplified */
+    int buf_done = 0;
+    uint64_t real_offset = data->real_offset;
+    uint64_t virtual_offset = data->virtual_offset - data->header_size;
+    uint64_t virtual_base = data->virtual_base;
+
+
+    if (data->config.sequence == 0)
+        data->config.sequence = 2;
+
+    /* read and transform Wwise Opus block into Ogg Opus block by making Ogg pages */
+    while (buf_done < buf_size) {
+        int bytes_to_copy, samples_per_frame;
+        size_t extra_size = 0, gap_size = 0;
+        size_t data_size = read_32bitBE(real_offset, data->streamfile);
+        /* 0x00: data size, 0x04: ?, 0x08+: data */
+
+        /* setup */
+        extra_size = 0x1b + (int)(data_size / 0xFF + 1); /* OggS page: base size + lacing values */
+        if (buf_done == 0) /* first read */
+            gap_size = virtual_offset - virtual_base; /* might start a few bytes into the block */
+
+        if (data_size + extra_size > 0x8000) {
+            VGM_LOG("WW OPUS: total size bigger than buffer at %lx\n", (off_t)real_offset);
+            return 0;
+        }
+
+        bytes_to_copy = data_size + extra_size - gap_size;
+        if (bytes_to_copy > buf_size - buf_done)
+            bytes_to_copy = buf_size - buf_done;
+
+        /* transform */
+        read_streamfile(v_buf + extra_size, real_offset + 0x08, data_size, data->streamfile);
+        samples_per_frame = get_opus_samples_per_frame(v_buf + extra_size, 48000); /* fixed? */
+        make_oggs_page(v_buf,0x8000, data_size, data->config.sequence, data->config.samples_done + samples_per_frame);
+        memcpy(buf + buf_done, v_buf + gap_size, bytes_to_copy);
+
+        /* move when block is fully done */
+        if (data_size + extra_size == bytes_to_copy + gap_size) {
+            real_offset += 0x04 + 0x04 + data_size;
+            virtual_base += data_size + extra_size;
+            data->config.sequence++;
+            data->config.samples_done += samples_per_frame;
+        }
+
+        buf_done += bytes_to_copy;
+    }
+
+    data->real_offset = real_offset;
+    data->virtual_base = virtual_base;
+    return buf_size;
+}
+
+int64_t ffmpeg_custom_seek_wwise_opus(ffmpeg_codec_data *data, int64_t virtual_offset) {
+    int64_t real_offset, virtual_base;
+    int64_t current_virtual_offset = data->virtual_offset;
+
+    /* find Wwise block start closest to offset; a 0x1E8 block expands to 0x1D + 0x1E0 (oggs + data) */
+
+    if (virtual_offset > current_virtual_offset) { /* seek after current: start from current block */
+        real_offset = data->real_offset;
+        virtual_base = data->virtual_base;
+    }
+    else { /* seek before current: start from the beginning */
+        real_offset = data->real_start;
+        virtual_base = 0;
+        data->config.sequence = 0;
+        data->config.samples_done = 0;
+    }
+
+
+    /* find target block */
+    while (virtual_base < virtual_offset) {
+        size_t extra_size;
+        size_t data_size = read_32bitBE(real_offset, data->streamfile);
+
+        extra_size = 0x1b + (int)(data_size / 0xFF + 1); /* OggS page: base size + lacing values */
+
+        /* stop if virtual_offset lands inside current block */
+        if (data_size + extra_size > virtual_offset)
+            break;
+
+        real_offset += 0x04 + 0x04 + data_size;
+        virtual_base += data_size + extra_size;
+    }
+
+    /* closest we can use for reads */
+    data->real_offset = real_offset;
+    data->virtual_base = virtual_base;
+
+    return virtual_offset;
+}
+
+int64_t ffmpeg_custom_size_wwise_opus(ffmpeg_codec_data *data) {
+    uint64_t real_offset = data->real_start;
+    uint64_t real_size = data->real_size;
+    uint64_t virtual_size = data->header_size;
+
+    /* count all Wwise Opus blocks size + OggS page size */
+    while (real_offset < real_size) {
+        size_t extra_size;
+        size_t data_size = read_32bitBE(real_offset, data->streamfile);
+        /* 0x00: data size, 0x04: ? (not a sequence or CRC), 0x08+: data */
+
+        extra_size = 0x1b + (int)(data_size / 0xFF + 1); /* OggS page: base size + lacing values */
+
+        real_offset += 0x04 + 0x04 + data_size;
+        virtual_size += extra_size + data_size;
+    }
+
+
+    return virtual_size;
+}
+
+
+
+/* ************************************************** */
+
+/* from ww2ogg - from Tremor (lowmem) */
+static uint32_t crc_lookup[256]={
+  0x00000000,0x04c11db7,0x09823b6e,0x0d4326d9,  0x130476dc,0x17c56b6b,0x1a864db2,0x1e475005,
+  0x2608edb8,0x22c9f00f,0x2f8ad6d6,0x2b4bcb61,  0x350c9b64,0x31cd86d3,0x3c8ea00a,0x384fbdbd,
+  0x4c11db70,0x48d0c6c7,0x4593e01e,0x4152fda9,  0x5f15adac,0x5bd4b01b,0x569796c2,0x52568b75,
+  0x6a1936c8,0x6ed82b7f,0x639b0da6,0x675a1011,  0x791d4014,0x7ddc5da3,0x709f7b7a,0x745e66cd,
+  0x9823b6e0,0x9ce2ab57,0x91a18d8e,0x95609039,  0x8b27c03c,0x8fe6dd8b,0x82a5fb52,0x8664e6e5,
+  0xbe2b5b58,0xbaea46ef,0xb7a96036,0xb3687d81,  0xad2f2d84,0xa9ee3033,0xa4ad16ea,0xa06c0b5d,
+  0xd4326d90,0xd0f37027,0xddb056fe,0xd9714b49,  0xc7361b4c,0xc3f706fb,0xceb42022,0xca753d95,
+  0xf23a8028,0xf6fb9d9f,0xfbb8bb46,0xff79a6f1,  0xe13ef6f4,0xe5ffeb43,0xe8bccd9a,0xec7dd02d,
+  0x34867077,0x30476dc0,0x3d044b19,0x39c556ae,  0x278206ab,0x23431b1c,0x2e003dc5,0x2ac12072,
+  0x128e9dcf,0x164f8078,0x1b0ca6a1,0x1fcdbb16,  0x018aeb13,0x054bf6a4,0x0808d07d,0x0cc9cdca,
+  0x7897ab07,0x7c56b6b0,0x71159069,0x75d48dde,  0x6b93dddb,0x6f52c06c,0x6211e6b5,0x66d0fb02,
+  0x5e9f46bf,0x5a5e5b08,0x571d7dd1,0x53dc6066,  0x4d9b3063,0x495a2dd4,0x44190b0d,0x40d816ba,
+  0xaca5c697,0xa864db20,0xa527fdf9,0xa1e6e04e,  0xbfa1b04b,0xbb60adfc,0xb6238b25,0xb2e29692,
+  0x8aad2b2f,0x8e6c3698,0x832f1041,0x87ee0df6,  0x99a95df3,0x9d684044,0x902b669d,0x94ea7b2a,
+  0xe0b41de7,0xe4750050,0xe9362689,0xedf73b3e,  0xf3b06b3b,0xf771768c,0xfa325055,0xfef34de2,
+  0xc6bcf05f,0xc27dede8,0xcf3ecb31,0xcbffd686,  0xd5b88683,0xd1799b34,0xdc3abded,0xd8fba05a,
+  0x690ce0ee,0x6dcdfd59,0x608edb80,0x644fc637,  0x7a089632,0x7ec98b85,0x738aad5c,0x774bb0eb,
+  0x4f040d56,0x4bc510e1,0x46863638,0x42472b8f,  0x5c007b8a,0x58c1663d,0x558240e4,0x51435d53,
+  0x251d3b9e,0x21dc2629,0x2c9f00f0,0x285e1d47,  0x36194d42,0x32d850f5,0x3f9b762c,0x3b5a6b9b,
+  0x0315d626,0x07d4cb91,0x0a97ed48,0x0e56f0ff,  0x1011a0fa,0x14d0bd4d,0x19939b94,0x1d528623,
+  0xf12f560e,0xf5ee4bb9,0xf8ad6d60,0xfc6c70d7,  0xe22b20d2,0xe6ea3d65,0xeba91bbc,0xef68060b,
+  0xd727bbb6,0xd3e6a601,0xdea580d8,0xda649d6f,  0xc423cd6a,0xc0e2d0dd,0xcda1f604,0xc960ebb3,
+  0xbd3e8d7e,0xb9ff90c9,0xb4bcb610,0xb07daba7,  0xae3afba2,0xaafbe615,0xa7b8c0cc,0xa379dd7b,
+  0x9b3660c6,0x9ff77d71,0x92b45ba8,0x9675461f,  0x8832161a,0x8cf30bad,0x81b02d74,0x857130c3,
+  0x5d8a9099,0x594b8d2e,0x5408abf7,0x50c9b640,  0x4e8ee645,0x4a4ffbf2,0x470cdd2b,0x43cdc09c,
+  0x7b827d21,0x7f436096,0x7200464f,0x76c15bf8,  0x68860bfd,0x6c47164a,0x61043093,0x65c52d24,
+  0x119b4be9,0x155a565e,0x18197087,0x1cd86d30,  0x029f3d35,0x065e2082,0x0b1d065b,0x0fdc1bec,
+  0x3793a651,0x3352bbe6,0x3e119d3f,0x3ad08088,  0x2497d08d,0x2056cd3a,0x2d15ebe3,0x29d4f654,
+  0xc5a92679,0xc1683bce,0xcc2b1d17,0xc8ea00a0,  0xd6ad50a5,0xd26c4d12,0xdf2f6bcb,0xdbee767c,
+  0xe3a1cbc1,0xe760d676,0xea23f0af,0xeee2ed18,  0xf0a5bd1d,0xf464a0aa,0xf9278673,0xfde69bc4,
+  0x89b8fd09,0x8d79e0be,0x803ac667,0x84fbdbd0,  0x9abc8bd5,0x9e7d9662,0x933eb0bb,0x97ffad0c,
+  0xafb010b1,0xab710d06,0xa6322bdf,0xa2f33668,  0xbcb4666d,0xb8757bda,0xb5365d03,0xb1f740b4
+};
+
+/* from ww2ogg */
+static uint32_t get_oggs_checksum(uint8_t * data, int bytes) {
+  uint32_t crc_reg=0;
+  int i;
+
+  for(i=0;i<bytes;++i)
+      crc_reg=(crc_reg<<8)^crc_lookup[((crc_reg >> 24)&0xff)^data[i]];
+
+  return crc_reg;
+}
+
+/* from opus_decoder.c */
+static uint32_t get_opus_samples_per_frame(const uint8_t * data, int Fs) {
+    int audiosize;
+    if (data[0]&0x80)
+    {
+       audiosize = ((data[0]>>3)&0x3);
+       audiosize = (Fs<<audiosize)/400;
+    } else if ((data[0]&0x60) == 0x60)
+    {
+       audiosize = (data[0]&0x08) ? Fs/50 : Fs/100;
+    } else {
+       audiosize = ((data[0]>>3)&0x3);
+       if (audiosize == 3)
+          audiosize = Fs*60/1000;
+       else
+          audiosize = (Fs<<audiosize)/100;
+    }
+    return audiosize;
+}
+
+
+static size_t make_oggs_page(uint8_t * buf, int buf_size, size_t data_size, int page_sequence, int granule) {
+    size_t page_done, lacing_done = 0;
+    uint64_t absolute_granule = granule; /* seem wrong values matter for Opus (0, less than real samples, etc) */
+    int header_type_flag = (page_sequence==0 ? 2 : 0);
+    int stream_serial_number = 0x7667; /* 0 is legal, but should be specified */
+    int checksum = 0;
+    int segment_count;
+
+
+    if (0x1b + (data_size/0xFF + 1) + data_size > buf_size) {
+        VGM_LOG("WW OPUS: buffer can't hold OggS page\n");
+        goto fail;
+    }
+
+    segment_count = (int)(data_size / 0xFF + 1);
+
+    put_32bitBE(buf+0x00, 0x4F676753); /* capture pattern ("OggS") */
+    put_8bit   (buf+0x04, 0); /* stream structure version, fixed */
+    put_8bit   (buf+0x05, header_type_flag); /* bitflags (0: normal, continued = 1, first = 2, last = 4) */
+    put_32bitLE(buf+0x06, (uint32_t)(absolute_granule >>  0 & 0xFFFFFFFF)); /* lower */
+    put_32bitLE(buf+0x0A, (uint32_t)(absolute_granule >> 32 & 0xFFFFFFFF)); /* upper */
+    put_32bitLE(buf+0x0E, stream_serial_number); /* for interleaved multi-streams */
+    put_32bitLE(buf+0x12, page_sequence);
+    put_32bitLE(buf+0x16, checksum); /* 0 for now, until all data is written */
+    put_8bit   (buf+0x1A, segment_count); /* count of all lacing values */
+
+    /* segment table: size N in "lacing values" (ex. 0x20E=0xFF+FF+10; 0xFF=0xFF+00) */
+    page_done = 0x1B;
+    while (lacing_done < data_size) {
+        int bytes = data_size - lacing_done;
+        if (bytes > 0xFF)
+            bytes = 0xFF;
+
+        put_8bit(buf+page_done, bytes);
+        page_done++;
+        lacing_done += bytes;
+
+        if (lacing_done == data_size && bytes == 0xFF) {
+            put_8bit(buf+page_done, 0x00);
+            page_done++;
+        }
+    }
+
+    /* data */
+    //memcpy(buf+page_done, data_buf, data_size); /* data must be copied before this call */
+    page_done += data_size;
+
+    /* final checksum */
+    checksum = get_oggs_checksum(buf, page_done);
+    put_32bitLE(buf+0x16, checksum);
+
+    return page_done;
+
+fail:
+    return 0;
+}
+
+static size_t make_opus_header(uint8_t * buf, int buf_size, int channels, int skip, int sample_rate) {
+    size_t header_size = 0x13;
+    int output_gain = 0;
+    int channel_papping_family = 0;
+
+    if (header_size > buf_size) {
+        VGM_LOG("WW OPUS: buffer can't hold header\n");
+        goto fail;
+    }
+
+    put_32bitBE(buf+0x00, 0x4F707573); /* header magic ("Opus") */
+    put_32bitBE(buf+0x04, 0x48656164); /* header magic ("Head") */
+    put_8bit   (buf+0x08, 1); /* version, fixed */
+    put_8bit   (buf+0x09, channels);
+    put_16bitLE(buf+0x0A, skip);
+    put_32bitLE(buf+0x0c, sample_rate);
+    put_16bitLE(buf+0x10, output_gain);
+    put_8bit   (buf+0x12, channel_papping_family);
+
+
+    return header_size;
+fail:
+    return 0;
+}
+
+static size_t make_opus_comment(uint8_t * buf, int buf_size) {
+    size_t comment_size;
+    int vendor_string_length, user_comment_0_length;
+    char * vendor_string = "libopus 1.0.2";
+    char * user_comment_0_string = "ENCODER=opusenc from opus-tools 0.1.6";
+    vendor_string_length = strlen(vendor_string);
+    user_comment_0_length = strlen(user_comment_0_string);
+
+    comment_size = 0x14 + vendor_string_length + user_comment_0_length;
+
+    if (comment_size > buf_size) {
+        VGM_LOG("WW OPUS: buffer can't hold comment\n");
+        goto fail;
+    }
+
+    put_32bitBE(buf+0x00, 0x4F707573); /* header magic ("Opus") */
+    put_32bitBE(buf+0x04, 0x54616773); /* header magic ("Tags") */
+    put_32bitLE(buf+0x08, vendor_string_length);
+    memcpy(buf+0x0c, vendor_string, vendor_string_length);
+    put_32bitLE(buf+0x0c + vendor_string_length+0x00, 1); /* user_comment_list_length */
+    put_32bitLE(buf+0x0c + vendor_string_length+0x04, user_comment_0_length);
+    memcpy(buf+0x0c + vendor_string_length+0x08, user_comment_0_string, user_comment_0_length);
+
+
+    return comment_size;
+fail:
+    return 0;
+}
+
+
+#endif
diff --git a/Frameworks/vgmstream/vgmstream/src/coding/pcm_decoder.c b/Frameworks/vgmstream/vgmstream/src/coding/pcm_decoder.c
index ea350ae3c..47c69cd09 100644
--- a/Frameworks/vgmstream/vgmstream/src/coding/pcm_decoder.c
+++ b/Frameworks/vgmstream/vgmstream/src/coding/pcm_decoder.c
@@ -1,5 +1,6 @@
 #include "coding.h"
 #include "../util.h"
+#include <math.h>
 
 void decode_pcm16LE(VGMSTREAMCHANNEL * stream, sample * outbuf, int channelspacing, int32_t first_sample, int32_t samples_to_do) {
     int i;
diff --git a/Frameworks/vgmstream/vgmstream/src/formats.c b/Frameworks/vgmstream/vgmstream/src/formats.c
index 7764ab401..658bc7b53 100644
--- a/Frameworks/vgmstream/vgmstream/src/formats.c
+++ b/Frameworks/vgmstream/vgmstream/src/formats.c
@@ -33,6 +33,7 @@ static const char* extension_list[] = {
     "aix",
     "akb",
     "amts", //fake extension (to be removed)
+    "ao", //txth/reserved [Cloudphobia (PC)]
     "as4",
     "asd",
     "asf",
@@ -85,6 +86,7 @@ static const char* extension_list[] = {
     "cps",
     "cxs",
 
+    "da",
     "dbm",
     "dcs",
     "ddsp",
@@ -135,6 +137,7 @@ static const char* extension_list[] = {
     "int",
     "isd",
     "isws",
+    "itl", //txth/reserved [Charinko Hero (GC)]
     "ivaud",
     "ivag",
     "ivb",
@@ -660,7 +663,7 @@ static const meta_info meta_info_list[] = {
         {meta_RIFF_WAVE_smpl,       "RIFF WAVE header with sample looping info"},
         {meta_RIFX_WAVE,            "RIFX WAVE header"},
         {meta_RIFX_WAVE_smpl,       "RIFX WAVE header with sample looping info"},
-        {meta_XNBm,                 "XNBm header"},
+        {meta_XNB,                  "Microsoft XNA Game Studio 4.0 header"},
         {meta_PCM_SCD,              "PCM file with custom header (SCD)"},
         {meta_PCM_PS2,              "PCM file with custom header (PS2)"},
         {meta_PS2_RKV,              "Legacy of Kain - Blood Omen 2 RKV Header"},
diff --git a/Frameworks/vgmstream/vgmstream/src/meta/bik.c b/Frameworks/vgmstream/vgmstream/src/meta/bik.c
index 20ca20ff9..f703b2a6a 100644
--- a/Frameworks/vgmstream/vgmstream/src/meta/bik.c
+++ b/Frameworks/vgmstream/vgmstream/src/meta/bik.c
@@ -34,8 +34,11 @@ VGMSTREAM * init_vgmstream_bik(STREAMFILE *streamFile) {
 
 #ifdef VGM_USE_FFMPEG
     {
-        /* init_FFmpeg uses streamFile->stream_index internally, if specified */
-        vgmstream->codec_data = init_ffmpeg_offset_index(streamFile, 0x0, get_streamfile_size(streamFile), stream_index);
+        ffmpeg_custom_config cfg;
+        memset(&cfg, 0, sizeof(ffmpeg_custom_config));
+        cfg.stream_index = stream_index;
+
+        vgmstream->codec_data = init_ffmpeg_config(streamFile, NULL,0, 0x0,get_streamfile_size(streamFile), &cfg);
         if (!vgmstream->codec_data) goto fail;
         vgmstream->coding_type = coding_FFmpeg;
     }
diff --git a/Frameworks/vgmstream/vgmstream/src/meta/ea_snu.c b/Frameworks/vgmstream/vgmstream/src/meta/ea_snu.c
index 722533333..c21a72523 100644
--- a/Frameworks/vgmstream/vgmstream/src/meta/ea_snu.c
+++ b/Frameworks/vgmstream/vgmstream/src/meta/ea_snu.c
@@ -1,27 +1,38 @@
 #include "meta.h"
 #include "../layout/layout.h"
+#include "../coding/coding.h"
 
-/* .SNU - EA new-ish header (Dead Space, The Godfather 2) */
+
+/* .SNU - from EA Redwood Shores/Visceral games (Dead Space, Dante's Inferno, The Godfather 2) */
 VGMSTREAM * init_vgmstream_ea_snu(STREAMFILE *streamFile) {
     VGMSTREAM * vgmstream = NULL;
     int channel_count, loop_flag = 0, channel_config, codec, sample_rate, flags;
     uint32_t num_samples, loop_start = 0, loop_end = 0;
     off_t start_offset;
+    int32_t (*read_32bit)(off_t,STREAMFILE*) = NULL;
 
 
     /* check extension, case insensitive */
     if (!check_extensions(streamFile,"snu"))
         goto fail;
 
-    /* check header */
-    //if ((read_32bitBE(0x00,streamFile) & 0x00FFFF00 != 0x00000000) && (read_32bitBE(0x0c,streamFile) != 0x00000000))
-    //    goto fail;
-    /* 0x00: related to sample rate?, 0x02: always 0?, 0x03: related to channels? (usually match but may be 0) */
-    /* 0x04: some size, maybe >>2 ~= number of 0x4c frames (BE/LE depending on platform) */
-    /* 0x08: always 0x20? (also BE/LE), 0x0c: always 0? */
+    /* check header (the first 0x10 are BE/LE depending on platform) */
+    /* 0x00(1): related to sample rate? (03=48000)
+     * 0x01(1): flags? (when set seems to be a bank and has extra data before start_offset) //todo
+     * 0x02(1): always 0?
+     * 0x03(1): channels? (usually matches but rarely may be 0)
+     * 0x04(4): some size, maybe >>2 ~= number of frames
+     * 0x08(4): start offset
+     * 0x0c(4): some sub-offset? (0x20, found when 0x01 is set) */
 
+    /* use start offset as endianness flag */
+    if ((uint32_t)read_32bitLE(0x08,streamFile) > 0x00F00000) {
+        read_32bit = read_32bitBE;
+    } else {
+        read_32bit = read_32bitLE;
+    }
 
-    start_offset = 0x20; /* first block */
+    start_offset = read_32bit(0x08,streamFile);
 
     codec = read_8bit(0x10,streamFile);
     channel_config = read_8bit(0x11,streamFile);
@@ -36,7 +47,7 @@ VGMSTREAM * init_vgmstream_ea_snu(STREAMFILE *streamFile) {
     }
 
 #if 0
-    //todo not working ok with blocks
+    //todo not working ok with blocks in XAS
     if (flags & 0x60) { /* full loop, seen in ambient tracks */
         loop_flag = 1;
         loop_start = 0;
@@ -45,7 +56,7 @@ VGMSTREAM * init_vgmstream_ea_snu(STREAMFILE *streamFile) {
 #endif
 
     //channel_count = (channel_config >> 2) + 1; //todo test
-    /* 01/02/03 = 1 ch?, 05/06/07 = 2/3 ch?, 0d/0e/0f = 4/5 ch?, 14/15/16/17 = 6/7 ch?, 1d/1e/1f = 8 ch? */
+    /* 01/02/03 = 1 ch?, 05/06/07 = 2/3 ch?, 0d/0e/0f = 4/5 ch?, 15/16/17 = 6/7 ch?, 1d/1e/1f = 8 ch? */
     switch(channel_config) {
         case 0x00: channel_count = 1; break;
         case 0x04: channel_count = 2; break;
@@ -68,20 +79,64 @@ VGMSTREAM * init_vgmstream_ea_snu(STREAMFILE *streamFile) {
     vgmstream->loop_end_sample = loop_end;
 
     vgmstream->meta_type = meta_EA_SNU;
-    vgmstream->layout_type = layout_ea_sns_blocked;
 
     switch(codec) {
-        case 0x04: /* "Xas1": EA-XAS (Dead Space) */
+        case 0x04:      /* "Xas1": EA-XAS (Dead Space) */
             vgmstream->coding_type = coding_EA_XAS;
+            vgmstream->layout_type = layout_ea_sns_blocked;
             break;
 
+#if 0
+#ifdef VGM_USE_MPEG
+        case 0x07: {    /* "EL32S": EALayer3 v2 "S" (Dante's Inferno PS3) */
+            mpeg_custom_config cfg;
+            off_t mpeg_start_offset = start_offset + 0x08;
+
+            memset(&cfg, 0, sizeof(mpeg_custom_config));
+
+            /* layout is still blocks, but should work fine with the custom mpeg decoder */
+            vgmstream->codec_data = init_mpeg_custom_codec_data(streamFile, mpeg_start_offset, &vgmstream->coding_type, vgmstream->channels, MPEG_EAL32S, &cfg);
+            if (!vgmstream->codec_data) goto fail;
+
+            vgmstream->layout_type = layout_ea_sns_blocked;
+            break;
+        }
+#endif
+#endif
+
+#ifdef VGM_USE_FFMPEG
+        case 0x03: {    /* "EXm0": EA-XMA (Dante's Inferno X360) */
+            uint8_t buf[0x100];
+            int bytes, block_size, block_count;
+            size_t stream_size, virtual_size;
+            ffmpeg_custom_config cfg;
+
+            stream_size = get_streamfile_size(streamFile) - start_offset;
+            virtual_size = ffmpeg_get_eaxma_virtual_size(start_offset,stream_size, streamFile);
+            block_size = 0x8000; /* ? */
+            block_count = stream_size / block_size + (stream_size % block_size ? 1 : 0);
+
+            bytes = ffmpeg_make_riff_xma2(buf, 0x100, vgmstream->num_samples, virtual_size, vgmstream->channels, vgmstream->sample_rate, block_count, block_size);
+            if (bytes <= 0) goto fail;
+
+            memset(&cfg, 0, sizeof(ffmpeg_custom_config));
+            cfg.type = FFMPEG_EA_XMA;
+            cfg.virtual_size = virtual_size;
+
+            vgmstream->codec_data = init_ffmpeg_config(streamFile, buf,bytes, start_offset,stream_size, &cfg);
+            if (!vgmstream->codec_data) goto fail;
+
+            vgmstream->coding_type = coding_FFmpeg;
+            vgmstream->layout_type = layout_none;
+            break;
+        }
+#endif
         case 0x00: /* "NONE" */
         case 0x01: /* not used? */
         case 0x02: /* "P6B0": PCM16BE */
-        case 0x03: /* "EXm0": EA-XMA */
+
         case 0x05: /* "EL31": EALayer3 v1 b (with PCM blocks in normal EA-frames?) */
         case 0x06: /* "EL32P": EALayer3 v2 "P" */
-        case 0x07: /* "EL32S": EALayer3 v2 "S" */
         case 0x09: /* EASpeex? */
         case 0x0c: /* EAOpus? */
         case 0x0e: /* XAS variant? */
@@ -97,7 +152,8 @@ VGMSTREAM * init_vgmstream_ea_snu(STREAMFILE *streamFile) {
     if (!vgmstream_open_stream(vgmstream,streamFile,start_offset))
         goto fail;
 
-    ea_sns_block_update(start_offset, vgmstream);
+    if (vgmstream->layout_type == layout_ea_sns_blocked)
+        ea_sns_block_update(start_offset, vgmstream);
 
     return vgmstream;
 
diff --git a/Frameworks/vgmstream/vgmstream/src/meta/hca_keys.h b/Frameworks/vgmstream/vgmstream/src/meta/hca_keys.h
index e3012873e..3d1cba9b4 100644
--- a/Frameworks/vgmstream/vgmstream/src/meta/hca_keys.h
+++ b/Frameworks/vgmstream/vgmstream/src/meta/hca_keys.h
@@ -100,6 +100,15 @@ static const hcakey_info hcakey_list[] = {
         // Yuyuyui (iOS/Android) *unconfirmed
         {4867249871962584729},      // 438BF1F883653699
 
+        // Tekken Mobile (iOS/Android)
+        {0xFFFFFFFFFFFFFFFF},       //
+
+        // Tales of the Rays (iOS/Android)
+        {9516284},                  // 00000000009134FC
+
+        // Skylock - Kamigami to Unmei no Itsutsuko [iOS]
+        {49160768297},              // 0000000B7235CB29
+
 };
 
 
diff --git a/Frameworks/vgmstream/vgmstream/src/meta/meta.h b/Frameworks/vgmstream/vgmstream/src/meta/meta.h
index f920bb111..fbbb0699c 100644
--- a/Frameworks/vgmstream/vgmstream/src/meta/meta.h
+++ b/Frameworks/vgmstream/vgmstream/src/meta/meta.h
@@ -144,9 +144,7 @@ VGMSTREAM * init_vgmstream_str_snds(STREAMFILE * streamFile);
 
 VGMSTREAM * init_vgmstream_ws_aud(STREAMFILE * streamFile);
 
-#ifdef VGM_USE_MPEG
 VGMSTREAM * init_vgmstream_ahx(STREAMFILE * streamFile);
-#endif
 
 VGMSTREAM * init_vgmstream_ivb(STREAMFILE * streamFile);
 
@@ -630,9 +628,7 @@ VGMSTREAM * init_vgmstream_ps2_svag_snk(STREAMFILE* streamFile);
 
 VGMSTREAM * init_vgmstream_xma(STREAMFILE* streamFile);
 
-#ifdef VGM_USE_FFMPEG
 VGMSTREAM * init_vgmstream_bik(STREAMFILE* streamFile);
-#endif
 
 VGMSTREAM * init_vgmstream_ps2_vds_vdm(STREAMFILE* streamFile);
 
diff --git a/Frameworks/vgmstream/vgmstream/src/meta/riff.c b/Frameworks/vgmstream/vgmstream/src/meta/riff.c
index e0ac857cc..e3933e4f9 100644
--- a/Frameworks/vgmstream/vgmstream/src/meta/riff.c
+++ b/Frameworks/vgmstream/vgmstream/src/meta/riff.c
@@ -2,6 +2,7 @@
 #include "../coding/coding.h"
 #include "../layout/layout.h"
 #include "../util.h"
+#include <string.h>
 
 /* Resource Interchange File Format */
 
@@ -262,7 +263,8 @@ VGMSTREAM * init_vgmstream_riff(STREAMFILE *streamFile) {
     /* check extension, case insensitive */
     streamFile->get_name(streamFile,filename,sizeof(filename));
     if (strcasecmp("wav",filename_extension(filename)) &&
-        strcasecmp("lwav",filename_extension(filename))
+        strcasecmp("lwav",filename_extension(filename)) &&
+        strcasecmp("da",filename_extension(filename)) /* SD Gundam - Over Galaxian, The Great Battle VI (PS) */
 #ifndef VGM_USE_FFMPEG
         && strcasecmp("sgb",filename_extension(filename)) /* SGB has proper support with FFmpeg in sgxd */
 #endif
@@ -835,79 +837,66 @@ fail:
     return NULL;
 }
 
-/* XNBm (Windows 7 Phone) */
+//todo move
+/* XNB - Microsoft XNA Game Studio 4.0 format */
 VGMSTREAM * init_vgmstream_xnbm(STREAMFILE *streamFile) {
     VGMSTREAM * vgmstream = NULL;
-    char filename[PATH_LIMIT];
+    off_t start_offset;
+    int loop_flag = 0, version, flags, num_samples = 0;
+    size_t xnb_size, data_size;
 
     struct riff_fmt_chunk fmt;
 
-    off_t file_size = -1;
-    int sample_count = 0;
-    off_t start_offset = -1;
-
-    int loop_flag = 0;
-#if 0
-    long loop_start_ms = -1;
-    long loop_end_ms = -1;
-    off_t loop_start_offset = -1;
-    off_t loop_end_offset = -1;
-#endif
-
-    uint32_t xnbm_size;
-    uint32_t data_size = 0;
 
     /* check extension, case insensitive */
-    streamFile->get_name(streamFile,filename,sizeof(filename));
-    if (strcasecmp("xnb",filename_extension(filename)))
-    {
+    if ( !check_extensions(streamFile,"xnb"))
         goto fail;
-    }
 
     /* check header */
-    if ((uint32_t)read_32bitBE(0,streamFile)!=0x584E426d) /* "XNBm" */
-        goto fail;
-    /* check version? */
-    if ((uint32_t)read_16bitLE(4,streamFile)!=5)
+    if ((read_32bitBE(0,streamFile) & 0xFFFFFF00) != 0x584E4200) /* "XNB" */
         goto fail;
+    /* 0x04: platform: ‘w’ = Microsoft Windows, ‘m’ = Windows Phone 7, ‘x’ = Xbox 360, 'a' = Android */
 
-    xnbm_size = read_32bitLE(6,streamFile);
-    file_size = get_streamfile_size(streamFile);
+    version = read_8bit(0x04,streamFile);
+    if (version != 5) goto fail; /* XNA 4.0 only */
 
-    /* check for tructated XNBm */
-    if (file_size < xnbm_size) goto fail;
+    flags = read_8bit(0x05,streamFile);
+    if (flags & 0x80) goto fail; /* compressed with XMemCompress, not public */
+    //if (flags & 0x01) goto fail; /* XMA flag? */
 
-    /* read through chunks to verify format and find metadata */
+    /* "check for truncated XNB" (???) */
+    xnb_size = read_32bitLE(0x06,streamFile);
+    if (get_streamfile_size(streamFile) < xnb_size) goto fail;
+
+    /* XNB contains "type reader" class references to parse "shared resource" data (can be any implemented filetype) */
     {
-        off_t current_chunk = 0xa; /* start with first chunk */
-        int id_string_len;
+        char reader_name[255+1];
+        off_t current_chunk = 0xa;
+        int reader_string_len;
         uint32_t fmt_chunk_size;
+        const char * type_sound =  "Microsoft.Xna.Framework.Content.SoundEffectReader"; /* partial "fmt" chunk or XMA */
+        //const char * type_song =  "Microsoft.Xna.Framework.Content.SongReader"; /* just references a companion .wma */
 
-        /* flag? count of strings? */
-        if (read_8bit(current_chunk ++, streamFile) != 1)
-            goto fail;
-
-        /* string length */
-        id_string_len = read_8bit(current_chunk ++, streamFile);
-
-        /* skip string */
-        /* may want to check this ID "Microsoft.Xna.Framework.Content.SoundEffectReader" */
-        current_chunk += id_string_len;
-
-        /* ???? */
-        if (read_32bitLE(current_chunk, streamFile) != 0)
-            goto fail;
-        current_chunk += 4;
-
-        /* ???? */
-        if (read_8bit(current_chunk ++, streamFile) != 0)
-            goto fail;
-
-        /* flag? count of chunks? */
+        /* type reader count, accept only one for now */
         if (read_8bit(current_chunk++, streamFile) != 1)
             goto fail;
 
-        /* fmt size */
+        reader_string_len = read_8bit(current_chunk++, streamFile); /* doesn't count null */
+        if (reader_string_len > 255) goto fail;
+
+        /* check SoundEffect type string */
+        if (read_string(reader_name,reader_string_len+1,current_chunk,streamFile) != reader_string_len)
+            goto fail;
+        if ( strcmp(reader_name, type_sound) != 0 )
+            goto fail;
+        current_chunk += reader_string_len + 1;
+        current_chunk += 4; /* reader version */
+
+        /* shared resource count */
+        if (read_8bit(current_chunk++, streamFile) != 1)
+            goto fail;
+
+        /* shared resource: partial "fmt" chunk */
         fmt_chunk_size = read_32bitLE(current_chunk, streamFile);
         current_chunk += 4;
 
@@ -918,10 +907,8 @@ VGMSTREAM * init_vgmstream_xnbm(STREAMFILE *streamFile) {
                   0,    /* sns == false */
                   0))   /* mwv == false */
                   goto fail;
-
         current_chunk += fmt_chunk_size;
 
-        /* data size! */
         data_size = read_32bitLE(current_chunk, streamFile);
         current_chunk += 4;
 
@@ -930,40 +917,40 @@ VGMSTREAM * init_vgmstream_xnbm(STREAMFILE *streamFile) {
 
     switch (fmt.coding_type) {
         case coding_PCM16LE:
-            sample_count = data_size/2/fmt.channel_count;
+            num_samples = pcm_bytes_to_samples(data_size, fmt.channel_count, 16);
             break;
         case coding_PCM8_U_int:
-            sample_count = data_size/fmt.channel_count;
+            num_samples = pcm_bytes_to_samples(data_size, fmt.channel_count, 8);
             break;
         case coding_MSADPCM:
-            sample_count = msadpcm_bytes_to_samples(data_size, fmt.block_size, fmt.channel_count);
+            num_samples = msadpcm_bytes_to_samples(data_size, fmt.block_size, fmt.channel_count);
             break;
         case coding_MS_IMA:
-            sample_count = (data_size / fmt.block_size) * (fmt.block_size - 4 * fmt.channel_count) * 2 / fmt.channel_count +
+            num_samples = (data_size / fmt.block_size) * (fmt.block_size - 4 * fmt.channel_count) * 2 / fmt.channel_count +
                 ((data_size % fmt.block_size) ? (data_size % fmt.block_size - 4 * fmt.channel_count) * 2 / fmt.channel_count : 0);
             break;
         default:
+            VGM_LOG("XNB: unknown codec 0x%x\n", fmt.coding_type);
             goto fail;
     }
 
-    /* build the VGMSTREAM */
 
+    /* build the VGMSTREAM */
     vgmstream = allocate_vgmstream(fmt.channel_count,loop_flag);
     if (!vgmstream) goto fail;
 
-    /* fill in the vital statistics */
-    vgmstream->num_samples = sample_count;
+    vgmstream->num_samples = num_samples;
     vgmstream->sample_rate = fmt.sample_rate;
 
+    vgmstream->meta_type = meta_XNB;
     vgmstream->coding_type = fmt.coding_type;
 
-    vgmstream->layout_type = layout_none;
     if (fmt.channel_count > 1) {
         switch (fmt.coding_type) {
             case coding_PCM8_U_int:
             case coding_MS_IMA:
             case coding_MSADPCM:
-                // use layout_none from above
+                vgmstream->layout_type = layout_none;
                 break;
             default:
                 vgmstream->layout_type = layout_interleave;
@@ -971,40 +958,24 @@ VGMSTREAM * init_vgmstream_xnbm(STREAMFILE *streamFile) {
         }
     }
 
-    vgmstream->interleave_block_size = fmt.interleave;
     switch (fmt.coding_type) {
         case coding_MSADPCM:
         case coding_MS_IMA:
-            // override interleave_block_size with frame size
             vgmstream->interleave_block_size = fmt.block_size;
             break;
         default:
-            // use interleave from above
+            vgmstream->interleave_block_size = fmt.interleave;
             break;
     }
 
-    vgmstream->meta_type = meta_XNBm;
 
-    /* open the file, set up each channel */
-    {
-        int i;
-
-        vgmstream->ch[0].streamfile = streamFile->open(streamFile,filename,
-                STREAMFILE_DEFAULT_BUFFER_SIZE);
-        if (!vgmstream->ch[0].streamfile) goto fail;
-
-        for (i=0;i<fmt.channel_count;i++) {
-            vgmstream->ch[i].streamfile = vgmstream->ch[0].streamfile;
-            vgmstream->ch[i].offset = vgmstream->ch[i].channel_start_offset =
-                start_offset+i*fmt.interleave;
-        }
-    }
+    if ( !vgmstream_open_stream(vgmstream,streamFile,start_offset) )
+        goto fail;
 
     return vgmstream;
 
-    /* clean up anything we may have opened */
 fail:
-    if (vgmstream) close_vgmstream(vgmstream);
+    close_vgmstream(vgmstream);
     return NULL;
 }
 
diff --git a/Frameworks/vgmstream/vgmstream/src/meta/txth.c b/Frameworks/vgmstream/vgmstream/src/meta/txth.c
index d75af34fd..1432ca9b4 100644
--- a/Frameworks/vgmstream/vgmstream/src/meta/txth.c
+++ b/Frameworks/vgmstream/vgmstream/src/meta/txth.c
@@ -289,6 +289,9 @@ found:
                 /* default FFmpeg */
                 ffmpeg_data = init_ffmpeg_offset(streamFile, txth.start_offset,txth.data_size);
                 if ( !ffmpeg_data ) goto fail;
+
+                if (vgmstream->num_samples == 0)
+                    vgmstream->num_samples = ffmpeg_data->totalSamples; /* sometimes works */
             }
             else {
                 /* fake header FFmpeg */
@@ -674,7 +677,7 @@ static int get_bytes_to_samples(txth_header * txth, uint32_t bytes) {
             return (bytes / txth->interleave) * (txth->interleave - 2) * 2;
 
         case MPEG: /* a bit complex */
-        case FFMPEG: /* too complex */
+        case FFMPEG: /* too complex, try after init */
         default:
             return 0;
     }
diff --git a/Frameworks/vgmstream/vgmstream/src/meta/wwise.c b/Frameworks/vgmstream/vgmstream/src/meta/wwise.c
index 173b8eb55..435377c9a 100644
--- a/Frameworks/vgmstream/vgmstream/src/meta/wwise.c
+++ b/Frameworks/vgmstream/vgmstream/src/meta/wwise.c
@@ -8,7 +8,7 @@
  *
  * Some info: https://www.audiokinetic.com/en/library/edge/
  */
-typedef enum { PCM, IMA, VORBIS, DSP, XMA2, XWMA, AAC, HEVAG, ATRAC9 } wwise_codec;
+typedef enum { PCM, IMA, VORBIS, DSP, XMA2, XWMA, AAC, HEVAG, ATRAC9, OPUS } wwise_codec;
 typedef struct {
     int big_endian;
     size_t file_size;
@@ -142,6 +142,7 @@ VGMSTREAM * init_vgmstream_wwise(STREAMFILE *streamFile) {
         case 0x0162: ww.codec = XWMA; break;
         case 0x0165: ww.codec = XMA2; break; /* always with the "XMA2" chunk, Wwise doesn't use XMA1 */
         case 0x0166: ww.codec = XMA2; break;
+        case 0x3039: ww.codec = OPUS; break;
         case 0xAAC0: ww.codec = AAC; break;
         case 0xFFF0: ww.codec = DSP; break;
         case 0xFFFB: ww.codec = HEVAG; break;
@@ -283,6 +284,8 @@ VGMSTREAM * init_vgmstream_wwise(STREAMFILE *streamFile) {
                     }
                 }
 
+                //ww.data_size -= audio_offset; //todo test
+
                 vgmstream->codec_data = init_vorbis_custom_codec_data(streamFile, start_offset + setup_offset, VORBIS_WWISE, &cfg);
                 if (!vgmstream->codec_data) goto fail;
             }
@@ -326,6 +329,7 @@ VGMSTREAM * init_vgmstream_wwise(STREAMFILE *streamFile) {
                         cfg.packet_type = STANDARD;
                 }
 
+                //ww.data_size -= audio_offset; //todo test
 
                 /* try with the selected codebooks */
                 vgmstream->codec_data = init_vorbis_custom_codec_data(streamFile, start_offset + setup_offset, VORBIS_WWISE, &cfg);
@@ -340,7 +344,7 @@ VGMSTREAM * init_vgmstream_wwise(STREAMFILE *streamFile) {
             vgmstream->coding_type = coding_VORBIS_custom;
             vgmstream->codec_endian = ww.big_endian;
 
-            start_offset = start_offset + audio_offset;
+            start_offset += audio_offset;
 
             /* Vorbis is VBR so this is very approximate, meh */
             if (ww.truncated)
@@ -467,11 +471,48 @@ VGMSTREAM * init_vgmstream_wwise(STREAMFILE *streamFile) {
             vgmstream->num_samples = ffmpeg_data->totalSamples;
             break;
         }
+
+        case OPUS: {    /* Switch */
+            uint8_t buf[0x100];
+            size_t bytes, skip;
+            ffmpeg_custom_config cfg;
+
+            /* values up to 0x14 seem fixed and similar to HEVAG's (block_align 0x02/04, bits_per_sample 0x10) */
+            if (ww.fmt_size == 0x28) {
+                size_t seek_size;
+
+                vgmstream->num_samples += read_32bit(ww.fmt_offset + 0x18, streamFile);
+                //todo 0x1c and 0x20: related to samples/looping?
+                seek_size = read_32bit(ww.fmt_offset + 0x24, streamFile);
+
+                start_offset += seek_size;
+                ww.data_size -= seek_size;
+            }
+            else {
+                goto fail;
+            }
+
+            skip = 0; /* Wwise doesn't seem to use it? (0x138 /0x3E8 ~default) */
+
+            bytes = ffmpeg_make_opus_header(buf,0x100, ww.channels, skip, ww.sample_rate);
+            if (bytes <= 0) goto fail;
+
+            memset(&cfg, 0, sizeof(ffmpeg_custom_config));
+            cfg.type = FFMPEG_WWISE_OPUS;
+            //cfg.big_endian = ww.big_endian; /* internally BE */
+
+            vgmstream->codec_data = init_ffmpeg_config(streamFile, buf,bytes, start_offset,ww.data_size, &cfg);
+            if (!vgmstream->codec_data) goto fail;
+
+            vgmstream->coding_type = coding_FFmpeg;
+            vgmstream->layout_type = layout_none;
+            break;
+        }
 #endif
         case HEVAG:     /* PSV */
             /* changed values, another bizarre Wwise quirk */
             //ww.block_align /* unknown (1ch=2, 2ch=4) */
-            //ww.bits_per_sample; /* probably interleave (0x10) */
+            //ww.bits_per_sample; /* unknown (0x10) */
             //if (ww.bits_per_sample != 4) goto fail;
 
             if (ww.big_endian) goto fail;
diff --git a/Frameworks/vgmstream/vgmstream/src/vgmstream.h b/Frameworks/vgmstream/vgmstream/src/vgmstream.h
index a7b2cda8f..d50a1e149 100644
--- a/Frameworks/vgmstream/vgmstream/src/vgmstream.h
+++ b/Frameworks/vgmstream/vgmstream/src/vgmstream.h
@@ -64,6 +64,7 @@ enum { STREAM_NAME_SIZE = 255 }; /* reasonable max */
 #ifdef VGM_USE_FFMPEG
 #include <libavcodec/avcodec.h>
 #include <libavformat/avformat.h>
+#include <libswresample/swresample.h>
 #endif
 
 #include "clHCA.h"
@@ -487,7 +488,7 @@ typedef enum {
     meta_RIFF_WAVE_SNS,     /* .sns RIFF */
     meta_RIFX_WAVE,         /* RIFX, for big-endian WAVs */
     meta_RIFX_WAVE_smpl,    /* RIFX w/ loop data in smpl chunk */
-    meta_XNBm,              /* XNBm, which has a RIFF fmt chunk */
+    meta_XNB,               /* XNA Game Studio 4.0 */
     meta_PC_MXST,           /* Lego Island MxSt */
 	meta_PC_SOB_SAB,		/* Worms 4 Mayhem SOB+SAB file */
     meta_NWA,               /* Visual Art's NWA */
@@ -1033,22 +1034,45 @@ typedef struct {
 } hca_codec_data;
 
 #ifdef VGM_USE_FFMPEG
+/* Custom FFMPEG modes */
+typedef enum {
+    FFMPEG_STANDARD,        /* default FFmpeg */
+    FFMPEG_WWISE_OPUS,      /* Opus without Ogg layer */
+    FFMPEG_EA_XMA,          /* XMA with padding removed in SNS blocks */
+  //FFMPEG_EA_SCHL,         /* Normal header+data (ex. ATRAC3) in SCxx blocks */
+  //FFMPEG_SFH,             /* ATRAC3plus header+data in SFH blocks */
+  //FFMPEG_AWC_XMA,         /* XMA data in AWC blocks, 1 streams per channel */
+} ffmpeg_custom_t;
+
+/* config for the above modes */
 typedef struct {
-    /*** init data ***/
+    int stream_index; /* FFmpeg's sub-stream (as opposed to an internal stream in custom read/seeks) */
+    int codec_endian;
+
+    ffmpeg_custom_t type; /* ffmpeg subtype */
+    size_t virtual_size; /* external value, if meta needs to know/supply it */
+
+    /* internal sequences, when needed */
+    int sequence;
+    int samples_done;
+} ffmpeg_custom_config;
+
+typedef struct {
+    /*** IO internals ***/
     STREAMFILE *streamfile;
+
+    uint64_t real_start;        // absolute start within the streamfile
+    uint64_t real_offset;       // absolute offset within the streamfile
+    uint64_t real_size;         // max size within the streamfile
+    uint64_t virtual_offset;    // computed offset FFmpeg sees (including fake header)
+    uint64_t virtual_size;      // computed size FFmpeg sees (including fake header)
+    uint64_t virtual_base;      // info/base virtual_offset equivalent to current real_offset (block aligned)
     
-    // offset and total size of raw stream data
-    uint64_t start;
-    uint64_t size;
-    
-    // offset into stream, includes header_size if header exists
-    uint64_t offset;
-    
-    // inserted header, ie. fake RIFF header
-    uint8_t *header_insert_block;
-    // header/fake RIFF over the real (parseable by FFmpeg) file start
-    uint64_t header_size;
-    
+    uint64_t header_size;       // fake header (parseable by FFmpeg) prepended on reads
+    uint8_t *header_insert_block; // fake header data (ie. RIFF)
+
+    ffmpeg_custom_config config; /* custom config/state */
+
     /*** "public" API (read-only) ***/
     // stream info
     int channels;
@@ -1088,6 +1112,8 @@ typedef struct {
     
     // Seeking is not ideal, so rollback is necessary
     int samplesToDiscard;
+
+
 } ffmpeg_codec_data;
 #endif