diff --git a/polymer/eduke32/build/src/sdlayer.c b/polymer/eduke32/build/src/sdlayer.c
index 82e9cd858..23d37a482 100644
--- a/polymer/eduke32/build/src/sdlayer.c
+++ b/polymer/eduke32/build/src/sdlayer.c
@@ -582,7 +582,7 @@ void grabmouse(char a)
         if (a != mouseacquired)
         {
 // #ifndef DEBUGGINGAIDS
-#if 1
+#if 0
             SDL_GrabMode g;
 
             g = SDL_WM_GrabInput(a ? SDL_GRAB_ON : SDL_GRAB_OFF);
diff --git a/polymer/eduke32/source/jaudiolib/src/driver_sdl.c b/polymer/eduke32/source/jaudiolib/src/driver_sdl.c
index 00cf4a062..82054ef38 100644
--- a/polymer/eduke32/source/jaudiolib/src/driver_sdl.c
+++ b/polymer/eduke32/source/jaudiolib/src/driver_sdl.c
@@ -25,6 +25,7 @@
 
 #include <SDL/SDL.h>
 #include <SDL/SDL_mixer.h>
+#include <SDL/SDL_thread.h>
 #include "driver_sdl.h"
 
 #ifndef UNREFERENCED_PARAMETER
@@ -54,7 +55,8 @@ static void ( *MixCallBack )( void ) = 0;
 
 static Mix_Chunk *DummyChunk = NULL;
 static uint8_t *DummyBuffer = NULL;
-// static int32_t InterruptsDisabled = 0;
+static int32_t InterruptsDisabled = 0;
+static SDL_mutex *EffectFence;
 
 static void fillData(int32_t chan, void *ptr, int32_t remaining, void *udata)
 {
@@ -64,6 +66,8 @@ static void fillData(int32_t chan, void *ptr, int32_t remaining, void *udata)
     UNREFERENCED_PARAMETER(chan);
     UNREFERENCED_PARAMETER(udata);
 
+    SDL_LockMutex(EffectFence);
+
 	while (remaining > 0) {
 		if (MixBufferUsed == MixBufferSize) {
 			MixCallBack();
@@ -90,6 +94,8 @@ static void fillData(int32_t chan, void *ptr, int32_t remaining, void *udata)
 			remaining -= len;
 		}
 	}
+
+    SDL_UnlockMutex(EffectFence);
 }
 
 
@@ -165,6 +171,8 @@ int32_t SDLDrv_PCM_Init(int32_t *mixrate, int32_t *numchannels, int32_t *sampleb
 
     //Mix_SetPostMix(fillData, NULL);
 
+    EffectFence = SDL_CreateMutex();
+
     // channel 0 and 1 are actual sounds
     // dummy channel 2 runs our fillData() callback as an effect
     Mix_RegisterEffect(2, fillData, NULL, NULL);
@@ -200,6 +208,9 @@ void SDLDrv_PCM_Shutdown(void)
     }
 
     Mix_CloseAudio();
+
+    SDL_DestroyMutex(EffectFence);
+
     Initialised = 0;
 }
 
@@ -245,21 +256,17 @@ void SDLDrv_PCM_StopPlayback(void)
 
 void SDLDrv_PCM_Lock(void)
 {
-/*
         if (InterruptsDisabled++)
             return;
     
-        SDL_LockAudio();*/
-    
+        SDL_LockMutex(EffectFence);
 }
 
 void SDLDrv_PCM_Unlock(void)
 {
-/*
         if (--InterruptsDisabled)
             return;
     
-        SDL_UnlockAudio();*/
-    
+        SDL_UnlockMutex(EffectFence);
 }