diff --git a/zsnes/src/cpu/dspproc.asm b/zsnes/src/cpu/dspproc.asm
index 57343b97..cbd30db5 100644
--- a/zsnes/src/cpu/dspproc.asm
+++ b/zsnes/src/cpu/dspproc.asm
@@ -516,11 +516,11 @@ EXTSYM MMXSupport
 
 NEWSYM AdjustFrequency
       mov al,[SoundInterpType]
+%ifndef __MSDOS__
       mov ah,[MMXSupport]
       cmp ah,0
       jne .mmx
-      cmp al,3
-      jne .mmx
+%endif
       mov al,1
       mov [SoundInterpType],al
 .mmx