diff --git a/desmume/src/cocoa/sndOSX.cpp b/desmume/src/cocoa/sndOSX.cpp
index 0245483a0..15e26d2a8 100644
--- a/desmume/src/cocoa/sndOSX.cpp
+++ b/desmume/src/cocoa/sndOSX.cpp
@@ -1,6 +1,6 @@
 /*
 	Copyright (C) 2007 Jeff Bland
-	Copyright (C) 2007-2011 DeSmuME team
+	Copyright (C) 2007-2012 DeSmuME team
 
 	This file is free software: you can redistribute it and/or modify
 	it under the terms of the GNU General Public License as published by
@@ -54,14 +54,11 @@ OSStatus soundMixer(void *inRefCon,
 					AudioBufferList *ioData)
 {
 //printf("SOUND CALLBACK %u off%u  pos%u\n", inNumberFrames * 4, sound_offset, sound_position);
+	UInt8 *__restrict__ outputData = (UInt8 *)ioData->mBuffers[0].mData;
 	const size_t copySize = inNumberFrames * SPU_STEREO_SAMPLE_SIZE;
 	size_t hiBufferAvailable = 0;
 	size_t loBufferAvailable = 0;
 	
-	pthread_mutex_lock(mutexAudioUnit);
-	
-	UInt8 *__restrict__ outputData = (UInt8 *)ioData->mBuffers[0].mData;
-	
 	pthread_mutex_lock(mutexSoundData);
 	
 	if(sound_data != NULL)
@@ -137,8 +134,6 @@ OSStatus soundMixer(void *inRefCon,
 		//ExtAudioFileWrite(outfile, inNumberFrames, ioData);
 	}
 	
-	pthread_mutex_unlock(mutexAudioUnit);
-	
 	return noErr;
 }