diff --git a/zsnes/src/cpu/dspproc.asm b/zsnes/src/cpu/dspproc.asm
index cbd30db5..f0fa9a8f 100644
--- a/zsnes/src/cpu/dspproc.asm
+++ b/zsnes/src/cpu/dspproc.asm
@@ -530,8 +530,10 @@ NEWSYM AdjustFrequency
       je near .cubicspline
       ja near .fir_mmx
       ; Copy from Gaussian to DSPInterP
+%ifndef __MSDOS__
       test ah,ah
       jne .gaussian_mmx
+%endif
       mov ebx,DSPInterP+1024
       mov edx,DSPInterP+1022
       mov esi,Gaussian