diff --git a/pt3_player/gr_fast_clear.s b/pt3_player/gr_fast_clear.s
index f804bc6f..f40c807c 100644
--- a/pt3_player/gr_fast_clear.s
+++ b/pt3_player/gr_fast_clear.s
@@ -5,7 +5,7 @@ clear_screens:
 
 	lda	#$0
 	jsr	clear_top
-	jsr	clear_bottom
+	jsr	clear_bottom0
 
 	;===================================
 	; Clear top/bottom of page 1
@@ -13,7 +13,7 @@ clear_screens:
 
 	lda	#$4
 	jsr	clear_top
-	jmp	clear_bottom
+	jmp	clear_bottom4
 
 
 
@@ -85,6 +85,7 @@ clear_bottoms:
 	; Clear bottom of page 1
 	;===================================
 
+clear_bottom4:
 	lda	#$4
 	; fall through
 
@@ -95,6 +96,7 @@ clear_bottoms:
 
 clear_bottom:
 	sta	DRAW_PAGE						; 3
+clear_bottom0:
 	clc								; 2
 
 	adc	#6							; 2
diff --git a/pt3_player/interrupt_handler.s b/pt3_player/interrupt_handler.s
index f7187d58..e48d7716 100644
--- a/pt3_player/interrupt_handler.s
+++ b/pt3_player/interrupt_handler.s
@@ -99,9 +99,9 @@ mb_not_13:
 	lda	#MOCK_AY_LATCH_ADDR	; latch_address for PB1		; 2
 	sta	MOCK_6522_ORB1		; latch_address on PB1          ; 4
 	sta	MOCK_6522_ORB2		; latch_address on PB2		; 4
-	lda	#MOCK_AY_INACTIVE	; go inactive			; 2
-	sta	MOCK_6522_ORB1						; 4
-	sta	MOCK_6522_ORB2						; 4
+	ldy	#MOCK_AY_INACTIVE	; go inactive			; 2
+	sty	MOCK_6522_ORB1						; 4
+	sty	MOCK_6522_ORB2						; 4
 
         ; value
 	lda	AY_REGISTERS,X		; load register value		; 4
@@ -110,11 +110,10 @@ mb_not_13:
 	lda	#MOCK_AY_WRITE		;				; 2
 	sta	MOCK_6522_ORB1		; write on PB1			; 4
 	sta	MOCK_6522_ORB2		; write on PB2			; 4
-	lda	#MOCK_AY_INACTIVE	; go inactive			; 2
-	sta	MOCK_6522_ORB1						; 4
-	sta	MOCK_6522_ORB2						; 4
+	sty	MOCK_6522_ORB1						; 4
+	sty	MOCK_6522_ORB2						; 4
 								;===========
-								; 	62
+								; 	60
 mb_no_write:
 	inx				; point to next register	; 2
 	cpx	#14			; if 14 we're done		; 2
@@ -178,7 +177,7 @@ done_time:
 check_keyboard:
 
 	jsr	get_key
-	lda	LASTKEY
+	cmp	#0
 	beq	exit_interrupt
 
 	;====================
diff --git a/pt3_player/keypress_minimal.s b/pt3_player/keypress_minimal.s
index 16d7c815..8b176a61 100644
--- a/pt3_player/keypress_minimal.s
+++ b/pt3_player/keypress_minimal.s
@@ -11,7 +11,7 @@ get_key:
 
 figure_out_key:
 	cmp	#' '+128		; the mask destroys space	; 2
-	beq	save_key		; so handle it specially	; 2nt/3
+	beq	return_key		; so handle it specially	; 2nt/3
 
 check_right_arrow:
 	cmp	#$95							; 2
@@ -32,15 +32,14 @@ check_down_arrow:
 check_escape:
 	and	#$5f			; mask, to make upper-case	; 2
         cmp	#$1B							; 2
-	bne	save_key						; 2nt/3
+	bne	return_key						; 2nt/3
 	lda	#'Q'							; 2
-	bne	save_key		; branch always			; 3
+	bne	return_key		; branch always			; 3
 
 no_key:
-	lda	#0			; no key, so save a zero	; 2
+	lda	#0			; no key, so return a zero	; 2
 
-save_key:
-	sta	LASTKEY			; save the key to our buffer	; 2
+return_key:
 	rts								; 6
 								;============
 
diff --git a/pt3_player/mockingboard_a.s b/pt3_player/mockingboard_a.s
index 67ddca70..bf8b7cdd 100644
--- a/pt3_player/mockingboard_a.s
+++ b/pt3_player/mockingboard_a.s
@@ -90,9 +90,9 @@ write_ay_both:
 	lda	#MOCK_AY_LATCH_ADDR	; latch_address on PB1		; 2
 	sta	MOCK_6522_ORB1		; latch_address on PB1		; 3
 	sta	MOCK_6522_ORB2		; latch_address on PB2		; 3
-	lda	#MOCK_AY_INACTIVE	; go inactive			; 2
-	sta	MOCK_6522_ORB1						; 3
-	sta	MOCK_6522_ORB2						; 3
+	ldy	#MOCK_AY_INACTIVE	; go inactive			; 2
+	sty	MOCK_6522_ORB1						; 3
+	sty	MOCK_6522_ORB2						; 3
 
 	; value
 	lda	MB_VALUE						; 3
@@ -101,13 +101,12 @@ write_ay_both:
 	lda	#MOCK_AY_WRITE		;				; 2
 	sta	MOCK_6522_ORB1		; write on PB1			; 3
 	sta	MOCK_6522_ORB2		; write on PB2			; 3
-	lda	#MOCK_AY_INACTIVE	; go inactive			; 2
-	sta	MOCK_6522_ORB1						; 3
-	sta	MOCK_6522_ORB2						; 3
+	sty	MOCK_6522_ORB1						; 3
+	sty	MOCK_6522_ORB2						; 3
 
 	rts								; 6
 								;===========
-								;       53
+								;       51
 	;=======================================
 	; clear ay -- clear all 14 AY registers
 	; should silence the card
diff --git a/pt3_player/pt3_lib.s b/pt3_player/pt3_lib.s
index bbb92cad..f6722cbe 100644
--- a/pt3_player/pt3_lib.s
+++ b/pt3_player/pt3_lib.s
@@ -497,7 +497,6 @@ VolTableCreator:
 
 	; Init initial variables
 	lda	#$0
-	sta	z80_h
 	sta	z80_d
 	ldy	#$11
 
@@ -524,14 +523,11 @@ vol_type_35:
 	ldy	#16		; skip first row, all zeros
 	ldx	#16		; c=16
 vol_outer:
-	lda	z80_h
-	pha			; save H
-
 	clc			; add HL,DE
 	lda	z80_l
 	adc	z80_e
 	sta	z80_e
-	lda	z80_h
+	lda	#0
 	adc	z80_d
 	sta	z80_d		; carry is important
 
@@ -572,8 +568,6 @@ vol_smc:
 
 
 	pla
-	pla
-	sta	z80_h	; restore H
 
 	lda	z80_e	; a=e
 	cmp	#$77
@@ -691,8 +685,9 @@ note_not_too_high:
 	;  a->tone = (a->tone + a->tone_sliding + w) & 0xfff;
 
 	clc
-	lda	note_a+NOTE_TONE_L,X
-	adc	note_a+NOTE_TONE_SLIDING_L,X
+	ldy	note_a+NOTE_TONE_SLIDING_L,X
+	tya
+	adc	note_a+NOTE_TONE_L,X
 	sta	note_a+NOTE_TONE_L,X
 	lda	note_a+NOTE_TONE_H,X
 	adc	note_a+NOTE_TONE_SLIDING_H,X
@@ -720,9 +715,10 @@ note_not_too_high:
 
 	; a->tone_sliding+=a->tone_slide_step
 	clc	;;can be removed if ADC freq_h cannot overflow
-	lda	note_a+NOTE_TONE_SLIDING_L,X
+	tya
 	adc	note_a+NOTE_TONE_SLIDE_STEP_L,X
 	sta	note_a+NOTE_TONE_SLIDING_L,X
+	tay
 	lda	note_a+NOTE_TONE_SLIDING_H,X
 	adc	note_a+NOTE_TONE_SLIDE_STEP_H,X
 	sta	note_a+NOTE_TONE_SLIDING_H,X
@@ -743,7 +739,7 @@ check1:
 	;				(a->tone_sliding <= a->tone_delta) ||
 
 	; 16 bit signed compare
-	lda	note_a+NOTE_TONE_SLIDING_L,X	; NUM1-NUM2
+	tya					; NUM1-NUM2
 	cmp	note_a+NOTE_TONE_DELTA_L,X	;
 	lda	note_a+NOTE_TONE_SLIDING_H,X
 	sbc	note_a+NOTE_TONE_DELTA_H,X
@@ -753,7 +749,7 @@ sc_loser1:
 	bmi	slide_to_note	; then A (signed) < NUM (signed) and BMI will branch
 
 	; equals case
-	lda	note_a+NOTE_TONE_SLIDING_L,X
+	tya
 	cmp	note_a+NOTE_TONE_DELTA_L,X
 	bne	check2
 	lda	note_a+NOTE_TONE_SLIDING_H,X
@@ -767,7 +763,7 @@ check2:
 	;				(a->tone_sliding >= a->tone_delta)
 
 	; 16 bit signed compare
-	lda	note_a+NOTE_TONE_SLIDING_L,X	; NUM1-NUM2
+	tya					; NUM1-NUM2
 	cmp	note_a+NOTE_TONE_DELTA_L,X	;
 	lda	note_a+NOTE_TONE_SLIDING_H,X
 	sbc	note_a+NOTE_TONE_DELTA_H,X
@@ -941,7 +937,6 @@ envelope_slide_done:
 
 	; a->envelope_sliding = j;
 	sta	note_a+NOTE_ENVELOPE_SLIDING,X
-	clc
 
 last_envelope:
 
diff --git a/pt3_player/pt3_timer.s b/pt3_player/pt3_timer.s
index 5ef887f7..6775d4c9 100644
--- a/pt3_player/pt3_timer.s
+++ b/pt3_player/pt3_timer.s
@@ -411,9 +411,9 @@ mb_not_13:
 	lda	#MOCK_AY_LATCH_ADDR	; latch_address for PB1		; 2
 	sta	MOCK_6522_ORB1		; latch_address on PB1          ; 4
 	sta	MOCK_6522_ORB2		; latch_address on PB2		; 4
-	lda	#MOCK_AY_INACTIVE	; go inactive			; 2
-	sta	MOCK_6522_ORB1						; 4
-	sta	MOCK_6522_ORB2						; 4
+	ldy	#MOCK_AY_INACTIVE	; go inactive			; 2
+	sty	MOCK_6522_ORB1						; 4
+	sty	MOCK_6522_ORB2						; 4
 
         ; value
 	lda	AY_REGISTERS,X		; load register value		; 4
@@ -422,11 +422,10 @@ mb_not_13:
 	lda	#MOCK_AY_WRITE		;				; 2
 	sta	MOCK_6522_ORB1		; write on PB1			; 4
 	sta	MOCK_6522_ORB2		; write on PB2			; 4
-	lda	#MOCK_AY_INACTIVE	; go inactive			; 2
-	sta	MOCK_6522_ORB1						; 4
-	sta	MOCK_6522_ORB2						; 4
+	sty	MOCK_6522_ORB1						; 4
+	sty	MOCK_6522_ORB2						; 4
 								;===========
-								; 	62
+								; 	60
 mb_no_write:
 	inx				; point to next register	; 2
 	cpx	#14			; if 14 we're done		; 2