diff --git a/sdk/include/reactos/libs/sound/mmebuddy_debug.h b/sdk/include/reactos/libs/sound/mmebuddy_debug.h
index 31f85c4dd34..0c6d7f8d77b 100644
--- a/sdk/include/reactos/libs/sound/mmebuddy_debug.h
+++ b/sdk/include/reactos/libs/sound/mmebuddy_debug.h
@@ -4,8 +4,9 @@
 /*
     Hacky debug macro
 */
+// TODO: Use a string-safe function instead of wsprintf().
 
-// FIXME: sdk\lib\...\mmebuddy compilation would fail: wsprintf() and MessageBox() are undefined!
+// FIXME: sdk\lib\...\mmebuddy compilation would fail: wsprintf() and MessageBoxW() are undefined!
 #if DBG && !defined(NDEBUG) // #if DBG
 
     // Helper for SND_ASSERT().
@@ -14,14 +15,14 @@
             WCHAR dbg_popup_msg[1024], dbg_popup_title[256]; \
             wsprintf(dbg_popup_title, L"%hS(%d)", __FILE__, __LINE__); \
             wsprintf(dbg_popup_msg, __VA_ARGS__); \
-            MessageBox(0, dbg_popup_msg, dbg_popup_title, MB_OK | MB_TASKMODAL); \
+            MessageBoxW(NULL, dbg_popup_msg, dbg_popup_title, MB_OK | MB_TASKMODAL); \
         }
 
     #define SND_ERR(...) \
         { \
             WCHAR dbg_popup_msg[1024]; \
             wsprintf(dbg_popup_msg, __VA_ARGS__); \
-            OutputDebugString(dbg_popup_msg); \
+            OutputDebugStringW(dbg_popup_msg); \
         }
 
     #define SND_ASSERT(condition) \
@@ -47,14 +48,14 @@
         { \
             WCHAR dbg_popup_msg[1024]; \
             wsprintf(dbg_popup_msg, __VA_ARGS__); \
-            OutputDebugString(dbg_popup_msg); \
+            OutputDebugStringW(dbg_popup_msg); \
         }
 
     #define SND_TRACE(...) \
         { \
             WCHAR dbg_popup_msg[1024]; \
             wsprintf(dbg_popup_msg, __VA_ARGS__); \
-            OutputDebugString(dbg_popup_msg); \
+            OutputDebugStringW(dbg_popup_msg); \
         }
 
     #define DUMP_WAVEHDR_QUEUE(sound_device_instance) \
@@ -74,7 +75,7 @@
 
     #define SND_WARN(...) do {} while ( 0 )
     #define SND_TRACE(...) do {} while ( 0 )
-    #define DUMP_WAVEHDR_QUEUE(condition) do {} while ( 0 )
+    #define DUMP_WAVEHDR_QUEUE(sound_device_instance) do {} while ( 0 )
 
 #endif // DBG && !defined(NDEBUG)