diff --git a/sdk/include/psdk/mmddk.h b/sdk/include/psdk/mmddk.h
index 70c0a84b982..fdb46d1c32a 100644
--- a/sdk/include/psdk/mmddk.h
+++ b/sdk/include/psdk/mmddk.h
@@ -91,6 +91,7 @@ typedef struct {
 #define DRV_QUERYSTRINGID		(DRV_RESERVED + 14)
 #define DRV_QUERYSTRINGIDSIZE		(DRV_RESERVED + 15)
 #define DRV_QUERYIDFROMSTRINGID		(DRV_RESERVED + 16)
+#define DRV_QUERYFUNCTIONINSTANCEID	(DRV_RESERVED + 17)
 #ifdef _WINE
 #define DRV_QUERYDSOUNDIFACE		(DRV_RESERVED + 20)
 #define DRV_QUERYDSOUNDDESC		(DRV_RESERVED + 21)