diff --git a/applecorn.po b/applecorn.po
index 41a1e88..2dd3dc7 100644
Binary files a/applecorn.po and b/applecorn.po differ
diff --git a/auxmem.init.s b/auxmem.init.s
index 9915aa7..c193116 100644
--- a/auxmem.init.s
+++ b/auxmem.init.s
@@ -290,7 +290,7 @@ BYTE00      BEQ   BYTE00A         ; OSBYTE 0,0 - generate error
             RTS                   ; %000x1xxx host type, 'A'pple
 BYTE00A     BRK
             DB    $F7
-HELLO       ASC   'Applecorn MOS 2022-11-20'
+HELLO       ASC   'Applecorn MOS 2022-11-21'
             DB    $00             ; Unify MOS messages
 * TO DO: Move into RAM
 GSSPEED     DB    $00             ; $80 if GS is fast, $00 for slow
diff --git a/auxmem.misc.s b/auxmem.misc.s
index c9ff86a..eef2097 100644
--- a/auxmem.misc.s
+++ b/auxmem.misc.s
@@ -380,15 +380,15 @@ GSBRKAUX    >>>   IENTAUX          ; IENTAUX does not do CLI
 IRQBRKHDLR  PHA
 * Mustn't enable IRQs within the IRQ handler
 * Do not use WRTMAIN/WRTAUX macros
-            LDA   RDRAMRD          ; Record softswitch state
-            STA   $90
-            LDA   RDRAMWR
-            STA   $91
-
-            STA   WRMAINRAM        ; Write to main memory
-            STA   $45              ; $45=A for ProDOS IRQ handlers
-            STA   WRCARDRAM        ; Write to aux memory
-            STA   RDCARDRAM        ; Read from aux memory
+*            LDA   RDRAMRD          ; Record softswitch state
+*            STA   $90
+*            LDA   RDRAMWR
+*            STA   $91
+*
+*            STA   WRMAINRAM        ; Write to main memory
+*            STA   $45              ; $45=A for ProDOS IRQ handlers
+*            STA   WRCARDRAM        ; Write to aux memory
+*            STA   RDCARDRAM        ; Read from aux memory
 
             PHX
             CLD
@@ -421,19 +421,20 @@ IRQBRKRET
             >>>   IENTAUX          ; IENTAUX does not do CLI
 
             PLY
-            LDA   $90              ; Restore state of RAMRD
-            BMI   :S1
-            STA   RDMAINRAM
-            BRA   :S2
-:S1         STA   RDCARDRAM
 
-:S2         LDA   $91              ; Restore state of RAMWRT
-            BMI   :S3
-            STA   WRMAINRAM
-            BRA   :S4
-:S3         STA   WRCARDRAM
+*            LDA   $90              ; Restore state of RAMRD
+*            BMI   :S1
+*            STA   RDMAINRAM
+*            BRA   :S2
+*:S1         STA   RDCARDRAM
+*
+*:S2         LDA   $91              ; Restore state of RAMWRT
+*            BMI   :S3
+*            STA   WRMAINRAM
+*            BRA   :S4
+*:S3         STA   WRCARDRAM
 
-:S4                                ; TODO: Pass on to IRQ1V
+*:S4                                ; TODO: Pass on to IRQ1V
             PLX
             PLA
 NULLRTI     RTI
diff --git a/mainmem.audio.s b/mainmem.audio.s
index 7bda744..f2e2cca 100644
--- a/mainmem.audio.s
+++ b/mainmem.audio.s
@@ -513,28 +513,33 @@ CHECK4BYTES PHX
 * Configure an oscillator to play a note
 * On entry: X - oscillator number 0-3 , A - frequency, Y - amplitude
 * Preserves all registers
-AUDIONOTE
+AUDIONOTE   PHA
+            LDA   AUDIOCARD
+            BEQ   :MOCK
+            PLA
             JMP  ENSQNOTE
-*            JMP  MOCKNOTE
-            RTS
+:MOCK       PLA
+            JMP  MOCKNOTE
 
 
 * Adjust frequency of  oscillator
 * On entry: X - oscillator number 0-3 , Y - frequency to set
 * Preserves X & Y
 AUDIOFREQ
+            LDA   AUDIOCARD
+            BEQ   :MOCK
             JMP  ENSQFREQ
-*            JMP  MOCKFREQ
-            RTS
+:MOCK       JMP  MOCKFREQ
 
 
 * Adjust amplitude of  oscillator
 * On entry: X - oscillator number 0-3 , Y - amplitude to set
 * Preserves X & Y
 AUDIOAMP
+            LDA   AUDIOCARD
+            BEQ   :MOCK
             JMP  ENSQAMP
-*            JMP  MOCKAMP
-            RTS
+:MOCK       JMP  MOCKAMP
 
 
 * Handle envelope tick counter
diff --git a/mainmem.init.s b/mainmem.init.s
index d43ea49..324c49d 100644
--- a/mainmem.init.s
+++ b/mainmem.init.s
@@ -6,6 +6,7 @@
 
 * 14-Nov-2021 If started from CSD, gets prefix to CMDBUF.
 
+AUDIOCARD    DB   $00                ; $00 = Mockingboard, $01 = Ensoniq
 
 * Trampoline in main memory used by aux memory IRQ handler
 * to invoke Apple II / ProDOS IRQs in main memory
@@ -34,10 +35,13 @@ RESET        TSX
 
 * Reset hardware
 RESETHW      SEC
+             STZ   AUDIOCARD
              JSR   IDROUTINE         ; See if this is a GS
              BCS   :NOTGS
              JSR   ENSQINIT          ; Initialize Ensoniq
+             INC   AUDIOCARD
+             RTS                     ; AUDIOCARD=1
 :NOTGS
-*             JSR   MOCKINIT          ; Initialize Mockingboard (sl4)
-             RTS
+             JSR   MOCKINIT          ; Initialize Mockingboard (sl4)
+             RTS                     ; AUDIOCARD=0
 
diff --git a/mame_applecorn b/mame_applecorn
index a21de9b..05ac8af 100755
--- a/mame_applecorn
+++ b/mame_applecorn
@@ -1,2 +1,2 @@
-#mame -w apple2ee -debug -sl5 mouse -sl7 cffa2 -harddisk1 ~/Personal/Development/Applecorn/applecorn.po
-mame -w apple2gs -debug -sl7 cffa2 -harddisk1 ~/Personal/Development/Applecorn/applecorn.po -harddisk2 tests/JGHMusic2.po
+mame -w apple2ee -debug -sl5 mouse -sl7 cffa2 -harddisk1 ~/Personal/Development/Applecorn/applecorn.po
+#mame -w apple2gs -debug -sl7 cffa2 -harddisk1 ~/Personal/Development/Applecorn/applecorn.po -harddisk2 tests/JGHMusic2.po