diff --git a/Audio/Chain/ConverterNode.h b/Audio/Chain/ConverterNode.h
index 7f671bda3..360d740e2 100644
--- a/Audio/Chain/ConverterNode.h
+++ b/Audio/Chain/ConverterNode.h
@@ -45,6 +45,8 @@
 
 	double sampleRatio;
 
+	BOOL observersAdded;
+
 	float volumeScale;
 
 	void *floatBuffer;
diff --git a/Audio/Chain/ConverterNode.m b/Audio/Chain/ConverterNode.m
index 1a3ff53ee..27dd75076 100644
--- a/Audio/Chain/ConverterNode.m
+++ b/Audio/Chain/ConverterNode.m
@@ -66,8 +66,6 @@ static void *kConverterNodeContext = &kConverterNodeContext;
 		extrapolateBuffer = NULL;
 		extrapolateBufferSize = 0;
 
-		[[NSUserDefaultsController sharedUserDefaultsController] addObserver:self forKeyPath:@"values.volumeScaling" options:0 context:kConverterNodeContext];
-
 #ifdef LOG_CHAINS
 		[self initLogFiles];
 #endif
@@ -76,6 +74,20 @@ static void *kConverterNodeContext = &kConverterNodeContext;
 	return self;
 }
 
+- (void)addObservers {
+	if(!observersAdded) {
+		[[NSUserDefaultsController sharedUserDefaultsController] addObserver:self forKeyPath:@"values.volumeScaling" options:(NSKeyValueObservingOptionInitial|NSKeyValueObservingOptionNew) context:kConverterNodeContext];
+		observersAdded = YES;
+	}
+}
+
+- (void)removeObservers {
+	if(observersAdded) {
+		[[NSUserDefaultsController sharedUserDefaultsController] removeObserver:self forKeyPath:@"values.volumeScaling" context:kConverterNodeContext];
+		observersAdded = NO;
+	}
+}
+
 void scale_by_volume(float *buffer, size_t count, float volume) {
 	if(volume != 1.0) {
 		size_t unaligned = (uintptr_t)buffer & 15;
@@ -334,6 +346,7 @@ void scale_by_volume(float *buffer, size_t count, float volume) {
 		if(nodeChannelConfig) {
 			[chunk setChannelConfig:nodeChannelConfig];
 		}
+		[self addObservers];
 		scale_by_volume(floatBuffer, ioNumberPackets / sizeof(float), volumeScale);
 		[chunk setStreamTimestamp:streamTimestamp];
 		[chunk setStreamTimeRatio:streamTimeRatio];
@@ -488,7 +501,7 @@ static float db_to_scale(float db) {
 - (void)dealloc {
 	DLog(@"Converter dealloc");
 
-	[[NSUserDefaultsController sharedUserDefaultsController] removeObserver:self forKeyPath:@"values.volumeScaling" context:kConverterNodeContext];
+	[self removeObservers];
 
 	paused = NO;
 	[self cleanUp];