diff --git a/src/emu/sound/rf5c400.c b/src/emu/sound/rf5c400.c
index 91f9cf0d761..730c6240056 100644
--- a/src/emu/sound/rf5c400.c
+++ b/src/emu/sound/rf5c400.c
@@ -413,6 +413,18 @@ WRITE16_MEMBER( rf5c400_device::rf5c400_w )
 			case 0x08:      // relative to env attack (channel no)
 			case 0x09:      // relative to env attack (0x0c00/ 0x1c00)
 
+			case 0x11:		// ? counter for 0x13?
+			{
+				break;
+			}
+			case 0x13:		// ? bujutsu writes sample data here
+			{
+				break;
+			}
+
+			case 0x14:		// ? related to 0x11/0x13 ?
+				break;
+
 			case 0x21:      // reverb(character).w
 			case 0x32:      // reverb(pre-lpf).w
 			case 0x2B:      // reverb(level).w