diff --git a/src/music/null_m.cpp b/src/music/null_m.cpp
--- a/src/music/null_m.cpp
+++ b/src/music/null_m.cpp
@@ -12,5 +12,5 @@
 #include "../stdafx.h"
 #include "null_m.h"
 
+/** The factory for the music player that does nothing. */
 static FMusicDriver_Null iFMusicDriver_Null;
-