diff --git a/Source/HBIOS/audio.inc b/Source/HBIOS/audio.inc
index e02e7af4..b6365494 100644
--- a/Source/HBIOS/audio.inc
+++ b/Source/HBIOS/audio.inc
@@ -34,4 +34,42 @@
 
 #IFNDEF AUDIOUTILS
 #DEFINE AUDIOUTILS
+
+AUD_NOTE:
+	AUDDEBUG("AUDNOTE ")
+	AUDTRACE_HL
+	AUDTRACE_CR
+	AUDTRACE_DE
+	AUDTRACE_CR
+
+	push	de
+	LD	DE, 48
+	CALL	DIV16
+					; BC IS OCTAVE COUNT
+					; HL is NOTE WITIN OCTAVE
+	ADD	HL, HL
+	pop	de
+	ADD	HL, DE
+
+	LD	A, (HL)			; RETRIEVE PERIOD COUNT FROM SN7NOTETBL
+	INC	HL
+	LD	H, (HL)
+	LD	L, A
+
+	INC	C
+AUD_NOTE1:
+	DEC	C
+	JR	Z, AUD_NOTE2
+	SRL	H
+  	RR	L
+	JR	AUD_NOTE1
+
+AUD_NOTE2:
+	LD	A, L			; IF NOT ZERO
+	OR	H
+	RET	NZ			; RETURN THE CALCULATED PERIOD
+
+	LD	H, $FF			; OTHERWISE RETURN -1 PERIOD (ERROR)
+	LD	L, $FF
+	RET
 #ENDIF
diff --git a/Source/HBIOS/ay38910.asm b/Source/HBIOS/ay38910.asm
index f0315f77..debe3e08 100644
--- a/Source/HBIOS/ay38910.asm
+++ b/Source/HBIOS/ay38910.asm
@@ -7,8 +7,6 @@
 ; @3.579545 OCTAVE RANGE IS 2 - 7 (Bb2/A#2 .. A7)
 ; @4.000000 OCTAVE RANGE IS 2 - 7 (B2 .. A7)
 ;
-;#include "cfg_state.inc"
-;
 AY_RCSND	.EQU	0		; 0 = EB MODULE, 1=MF MODULE
 ;
 #IF (AYMODE == AYMODE_SCG)
@@ -70,8 +68,6 @@ AY_IDAT	.EQU	0			; NO INSTANCE DATA ASSOCIATED WITH THIS DEVICE
 ;
 ;	DEVICE CAPABILITIES AND CONFIGURATION
 ;
-SBCV2004	.EQU	0		; USE SBC-V2-004 HALF CLOCK DIVIDER
-;
 AY_TONECNT	.EQU	3		; COUNT NUMBER OF TONE CHANNELS
 AY_NOISECNT	.EQU	1		; COUNT NUMBER OF NOISE CHANNELS
 ;
@@ -459,7 +455,7 @@ AY_EI:
 ;
 AY_WRTPSG:
 	CALL	AY_DI
-#IF (SBCV2004)
+#IFDEF SBCV2004
 	LD	A,8			; SBC-V2-004 CHANGE
 	OUT	(112),A			; TO HALF CLOCK SPEED
 #ENDIF
@@ -477,7 +473,7 @@ AY_WRTPSG:
 	POP	AF			; GET SAVED DCNTL VALUE
 	OUT0	(Z180_DCNTL),A		; AND RESTORE IT
 #ENDIF
-#IF (SBCV2004)
+#IFDEF SBCV2004
 	LD	A,0			; SBC-V2-004 CHANGE TO
 	OUT	(112),A			; NORMAL CLOCK SPEED
 #ENDIF
@@ -489,7 +485,7 @@ AY_WRTPSG:
 ;
 AY_RDPSG:
 	CALL	AY_DI
-#IF (SBCV2004)
+#IFDEF SBCV2004
 	LD	A,8			; SBC-V2-004 CHANGE
 	OUT	(112),A			; TO HALF CLOCK SPEED
 #ENDIF
@@ -507,7 +503,7 @@ AY_RDPSG:
 	POP	AF			; GET SAVED DCNTL VALUE
 	OUT0	(Z180_DCNTL),A		; AND RESTORE IT
 #ENDIF
-#IF (SBCV2004)
+#IFDEF SBCV2004
 	LD	A,0			; SBC-V2-004 CHANGE TO
 	OUT	(112),A			; NORMAL CLOCK SPEED
 #ENDIF
diff --git a/Source/HBIOS/sn76489.asm b/Source/HBIOS/sn76489.asm
index d1b784cc..220e07e3 100644
--- a/Source/HBIOS/sn76489.asm
+++ b/Source/HBIOS/sn76489.asm
@@ -24,8 +24,7 @@ CHANNEL_1_SILENT	.EQU	$BF
 CHANNEL_2_SILENT	.EQU	$DF
 CHANNEL_3_SILENT	.EQU	$FF
 
-SN7_SCALE	.EQU	4	
-SN7RATIO	.EQU	(SN7CLK * 100) / (32 >> SN7_SCALE)
+SN7RATIO	.EQU	SN7CLK * 100 / 32
 
 	.ECHO	"SN76489 CLOCK: "
 	.ECHO	SN7CLK
@@ -105,42 +104,9 @@ SN7_VOLUME:
 	RET
 
 SN7_NOTE:
-
-;	CALL	PRTHEXWORDHL
-;	CALL	PC_COLON
-
-	AUDDEBUG("AUDNOTE ")
-	AUDTRACE_HL
-	AUDTRACE_CR
-	AUDTRACE_DE
-	AUDTRACE_CR
-
 	LD	DE, SN7NOTETBL
-	PUSH	DE			; ON ENTRY HL IS THE NOTE TO PLAY
-	LD	DE, 48			; AND DE IS THE START OF NOTE TABLE
-	CALL	DIV16			; LOAD DE WITH NOTE TABLE SIZE
-					; AND CALCULATE OCTAVE COUNT IN BC
-
-	ADD	HL, HL			; HL IS THE REMAINDER FROM ABOVE DIVISION (0-47) AND THE NOTE 
-	POP	DE			; TO PLAY IN THE OCTAVE. ADD IT TO THE START OF THE NOTE TABLE
-	ADD	HL, DE			; TO POINT TO THE PERIOD FOR THE NOTE WE WANT TO PLAY.
-
-	LD	A, (HL)			; HL POINT TO CURRENT PERIOD COUNT WE WANT TO PLAY
-	INC	HL			; SO LOAD PERIOD COUNT FROM NOTE TABLE INTO HL
-	LD	H, (HL)			; SO WE CAN UPDATE IT FOR THE REQUIRED OCTAVE
-	LD	L, A
-
-	LD	A,SN7_SCALE		; THE NOTE TABLE PERIOD DATA HAS BEEN
-	ADD	A,C			; PRESCALED TO MAINTAIN RANGE SO ALLOW
-	LD	B,A			; FOR THIS WHEN CHANGING OCTAVE
-SN7_NOTE1:
-	SRL	H			; ADJUST THE PERIOD DATA
-  	RR	L			; FOR THE DESIRED OCTAVE
-	DJNZ	SN7_NOTE1		; FALL THROUGH TO SET PERIOD AND RANGE CHECK
-
-;	CALL	PRTHEXWORDHL
-;	CALL	NEWLINE
-
+	CALL	AUD_NOTE		; RETURNS PERIOD IN HL, FALL THRU
+					; TO SET THIS PERIOD
 SN7_PERIOD:
 	AUDTRACE(SNT_PERIOD)
 	AUDTRACE_HL