diff --git a/apps/openmw/mwsound/soundmanager.cpp b/apps/openmw/mwsound/soundmanager.cpp
index a46c17e79..5a6b07e0a 100644
--- a/apps/openmw/mwsound/soundmanager.cpp
+++ b/apps/openmw/mwsound/soundmanager.cpp
@@ -23,13 +23,17 @@
 */
 #ifdef OPENMW_USE_FFMPEG
 #include "ffmpeg_decoder.hpp"
+#ifndef SOUND_IN
 #define SOUND_IN "FFmpeg"
 #endif
+#endif
 
 #ifdef OPENMW_USE_MPG123
 #include "mpgsnd_decoder.hpp"
+#ifndef SOUND_IN
 #define SOUND_IN "mpg123,sndfile"
 #endif
+#endif
 
 
 namespace MWSound