diff --git a/Source/HBIOS/hbios.asm b/Source/HBIOS/hbios.asm
index f1aa9ab3..4b50cdb0 100644
--- a/Source/HBIOS/hbios.asm
+++ b/Source/HBIOS/hbios.asm
@@ -4165,7 +4165,12 @@ PS_SOUND:
 	LD	E,BF_SNDQ_DEV
 	RST	08
 	LD	A,B
-	DEC	A
+	;DEC	A
+	RLCA
+	RLCA
+	RLCA
+	RLCA
+	AND	$0F
 	LD	DE,PS_SDSN76489
 	CALL	PRTIDXDEA
 	LD	A,(PRTIDXCNT)