diff --git a/Plugins/Opus/Opus/OpusDecoder.m b/Plugins/Opus/Opus/OpusDecoder.m
index c4ae3b3be..e588161fc 100644
--- a/Plugins/Opus/Opus/OpusDecoder.m
+++ b/Plugins/Opus/Opus/OpusDecoder.m
@@ -14,6 +14,18 @@
 
 @implementation OpusFile
 
+static const int MAXCHANNELS = 8;
+static const int chmap[MAXCHANNELS][MAXCHANNELS] = {
+    { 0, },                    // mono
+    { 0, 1, },                 // l, r
+    { 0, 2, 1, },              // l, c, r -> l, r, c
+    { 0, 1, 2, 3, },           // l, r, bl, br
+    { 0, 2, 1, 3, 4, },        // l, c, r, bl, br -> l, r, c, bl, br
+    { 0, 2, 1, 5, 3, 4 },      // l, c, r, bl, br, lfe -> l, r, c, lfe, bl, br
+    { 0, 2, 1, 6, 5, 3, 4 },   // l, c, r, sl, sr, bc, lfe -> l, r, c, lfe, bc, sl, sr
+    { 0, 2, 1, 7, 5, 6, 3, 4 } // l, c, r, sl, sr, bl, br, lfe -> l, r, c, lfe, bl, br, sl, sr
+};
+
 int sourceRead(void *_stream, unsigned char *_ptr, int _nbytes)
 {
 	id source = (__bridge id)_stream;
@@ -100,8 +112,19 @@ opus_int64 sourceTell(void *_stream)
     int size = frames * channels;
     
     do {
+        float *out = ((float*)buf) + total;
+        float tempbuf[512 * channels];
 		lastSection = currentSection;
-        numread = op_read_float( opusRef, &((float *)buf)[total], size - total, NULL );
+        int toread = size - total;
+        if (toread > 512) toread = 512;
+        numread = op_read_float( opusRef, (channels < MAXCHANNELS) ? tempbuf : out, toread, NULL );
+        if (numread > 0 && channels < MAXCHANNELS) {
+            for (int i = 0; i < numread; ++i) {
+                for (int j = 0; j < channels; ++j) {
+                    out[i * channels + j] = tempbuf[i * channels + chmap[channels - 1][j]];
+                }
+            }
+        }
         currentSection = op_current_link( opusRef );
 		if (numread > 0) {
 			total += numread * channels;
@@ -111,7 +134,7 @@ opus_int64 sourceTell(void *_stream)
 			break;
 		}
 		
-    } while (total != frames && numread != 0);
+    } while (total != size && numread != 0);
 
     return total/channels;
 }
diff --git a/Plugins/Vorbis/VorbisDecoder.m b/Plugins/Vorbis/VorbisDecoder.m
index 2ca1a30cd..ea53a09e9 100644
--- a/Plugins/Vorbis/VorbisDecoder.m
+++ b/Plugins/Vorbis/VorbisDecoder.m
@@ -12,6 +12,18 @@
 
 @implementation VorbisDecoder
 
+static const int MAXCHANNELS = 8;
+static const int chmap[MAXCHANNELS][MAXCHANNELS] = {
+    { 0, },                    // mono
+    { 0, 1, },                 // l, r
+    { 0, 2, 1, },              // l, c, r -> l, r, c
+    { 0, 1, 2, 3, },           // l, r, bl, br
+    { 0, 2, 1, 3, 4, },        // l, c, r, bl, br -> l, r, c, bl, br
+    { 0, 2, 1, 5, 3, 4 },      // l, c, r, bl, br, lfe -> l, r, c, lfe, bl, br
+    { 0, 2, 1, 6, 5, 3, 4 },   // l, c, r, sl, sr, bc, lfe -> l, r, c, lfe, bc, sl, sr
+    { 0, 2, 1, 7, 5, 6, 3, 4 } // l, c, r, sl, sr, bl, br, lfe -> l, r, c, lfe, bl, br, sl, sr
+};
+
 size_t sourceRead(void *buf, size_t size, size_t nmemb, void *datasource)
 {
 	id source = (__bridge id)datasource;
@@ -94,9 +106,18 @@ long sourceTell(void *datasource)
         float ** pcm;
         numread = (int)ov_read_float(&vorbisRef, &pcm, frames - total, &currentSection);
 		if (numread > 0) {
-            for (int i = 0; i < channels; i++) {
-                for (int j = 0; j < numread; j++) {
-                    ((float *)buf)[(total + j) * channels + i] = pcm[i][j];
+            if (channels < MAXCHANNELS) {
+                for (int i = 0; i < channels; i++) {
+                    for (int j = 0; j < numread; j++) {
+                        ((float *)buf)[(total + j) * channels + i] = pcm[chmap[channels-1][i]][j];
+                    }
+                }
+            }
+            else {
+                for (int i = 0; i < channels; i++) {
+                    for (int j = 0; j < numread; j++) {
+                        ((float *)buf)[(total + j) * channels + i] = pcm[i][j];
+                    }
                 }
             }
 			total += numread;