diff --git a/Source/HBIOS/hbios.asm b/Source/HBIOS/hbios.asm
index 979b86b8..9a4c5073 100644
--- a/Source/HBIOS/hbios.asm
+++ b/Source/HBIOS/hbios.asm
@@ -2286,7 +2286,7 @@ SND_ADDENT:
 ;	WORD	UNIT SPECIFIC DATA (TYPICALLY A DEVICE INSTANCE DATA ADDRESS)
 ;
 SND_FNCNT	.EQU	6		; NUMBER OF SND FUNCS (FOR RANGE CHECK)
-SND_MAX		.EQU	2		; UP TO 2 UNITS
+SND_MAX		.EQU	3		; UP TO 2 UNITS
 SND_SIZ		.EQU	SND_MAX * 4	; EACH ENTRY IS 4 BYTES
 ;
 		.DB	SND_FNCNT	; SND FUNCTION COUNT (FOR RANGE CHECK)