diff --git a/dlls/winecoreaudio.drv/coreaudio.h b/dlls/winecoreaudio.drv/coreaudio.h
index 485c65336ac..4cf2b03c885 100644
--- a/dlls/winecoreaudio.drv/coreaudio.h
+++ b/dlls/winecoreaudio.drv/coreaudio.h
@@ -26,7 +26,7 @@ extern LONG CoreAudio_WaveInit(void);
 extern void CoreAudio_WaveRelease(void);
 
 extern LONG CoreAudio_MIDIInit(void);
-extern void CoreAudio_MIDIRelease(void);
+extern LONG CoreAudio_MIDIRelease(void);
 
 extern LONG CoreAudio_MixerInit(void);
 extern void CoreAudio_MixerRelease(void);