diff --git a/dlls/dmband/dmband_private.h b/dlls/dmband/dmband_private.h
index 46a4d079cc8..aa775dfc9ad 100644
--- a/dlls/dmband/dmband_private.h
+++ b/dlls/dmband/dmband_private.h
@@ -52,9 +52,9 @@ typedef struct IDirectMusicBandTrack IDirectMusicBandTrack;
 /*****************************************************************************
  * ClassFactory
  */
-extern HRESULT WINAPI DMUSIC_CreateDirectMusicBandImpl (LPCGUID lpcGUID, LPVOID* ppobj, LPUNKNOWN pUnkOuter);
+extern HRESULT WINAPI DMUSIC_CreateDirectMusicBandImpl (LPCGUID lpcGUID, LPVOID* ppobj, LPUNKNOWN pUnkOuter) DECLSPEC_HIDDEN;
 
-extern HRESULT WINAPI DMUSIC_CreateDirectMusicBandTrack (LPCGUID lpcGUID, LPVOID* ppobj, LPUNKNOWN pUnkOuter);
+extern HRESULT WINAPI DMUSIC_CreateDirectMusicBandTrack (LPCGUID lpcGUID, LPVOID* ppobj, LPUNKNOWN pUnkOuter) DECLSPEC_HIDDEN;
 
 
 /*****************************************************************************
@@ -121,7 +121,7 @@ struct IDirectMusicBandTrack {
 /**********************************************************************
  * Dll lifetime tracking declaration for dmband.dll
  */
-extern LONG DMBAND_refCount;
+extern LONG DMBAND_refCount DECLSPEC_HIDDEN;
 static inline void DMBAND_LockModule(void) { InterlockedIncrement( &DMBAND_refCount ); }
 static inline void DMBAND_UnlockModule(void) { InterlockedDecrement( &DMBAND_refCount ); }
 
diff --git a/dlls/dmband/dmutils.h b/dlls/dmband/dmutils.h
index 6195220417f..82706d647e0 100644
--- a/dlls/dmband/dmutils.h
+++ b/dlls/dmband/dmutils.h
@@ -32,9 +32,9 @@ typedef struct _DMUS_PRIVATE_CHUNK {
 /**
  * Parsing utilities
  */
-extern HRESULT IDirectMusicUtils_IPersistStream_ParseDescGeneric (DMUS_PRIVATE_CHUNK* pChunk, IStream* pStm, LPDMUS_OBJECTDESC pDesc);
-extern HRESULT IDirectMusicUtils_IPersistStream_ParseUNFOGeneric (DMUS_PRIVATE_CHUNK* pChunk, IStream* pStm, LPDMUS_OBJECTDESC pDesc);
-extern HRESULT IDirectMusicUtils_IPersistStream_ParseReference (LPPERSISTSTREAM iface, DMUS_PRIVATE_CHUNK* pChunk, IStream* pStm, IDirectMusicObject** ppObject);
+extern HRESULT IDirectMusicUtils_IPersistStream_ParseDescGeneric (DMUS_PRIVATE_CHUNK* pChunk, IStream* pStm, LPDMUS_OBJECTDESC pDesc) DECLSPEC_HIDDEN;
+extern HRESULT IDirectMusicUtils_IPersistStream_ParseUNFOGeneric (DMUS_PRIVATE_CHUNK* pChunk, IStream* pStm, LPDMUS_OBJECTDESC pDesc) DECLSPEC_HIDDEN;
+extern HRESULT IDirectMusicUtils_IPersistStream_ParseReference (LPPERSISTSTREAM iface, DMUS_PRIVATE_CHUNK* pChunk, IStream* pStm, IDirectMusicObject** ppObject) DECLSPEC_HIDDEN;
 
 /**
  * Debug utilities
@@ -61,10 +61,10 @@ typedef struct {
 #define GE(x) { &x, #x }
 
 /* FOURCC to string conversion for debug messages */
-extern const char *debugstr_fourcc (DWORD fourcc);
+extern const char *debugstr_fourcc (DWORD fourcc) DECLSPEC_HIDDEN;
 /* returns name of given GUID */
-extern const char *debugstr_dmguid (const GUID *id);
+extern const char *debugstr_dmguid (const GUID *id) DECLSPEC_HIDDEN;
 
-extern void        debug_DMUS_OBJECTDESC (LPDMUS_OBJECTDESC pDesc);
+extern void        debug_DMUS_OBJECTDESC (LPDMUS_OBJECTDESC pDesc) DECLSPEC_HIDDEN;
 
 #endif /* __WINE_DMUTILS_H */