diff --git a/src/sound/null_s.h b/src/sound/null_s.h
--- a/src/sound/null_s.h
+++ b/src/sound/null_s.h
@@ -7,8 +7,6 @@
 
 class SoundDriver_Null: public SoundDriver {
 public:
-	/* virtual */ bool CanProbe() { return false; }
-
 	/* virtual */ const char *Start(const char * const *param) { return NULL; }
 
 	/* virtual */ void Stop() { }
@@ -16,6 +14,7 @@ public:
 
 class FSoundDriver_Null: public SoundDriverFactory<FSoundDriver_Null> {
 public:
+	static const int priority = 0;
 	/* virtual */ const char *GetName() { return "null"; }
 	/* virtual */ const char *GetDescription() { return "Null Sound Driver"; }
 	/* virtual */ Driver *CreateInstance() { return new SoundDriver_Null(); }