fix sfx duration change

Author: msaarna

includes/std_routines.asm

@@ -750,14 +750,11 @@ servicesfxchannelsloop
      jmp servicesfxchannelsloop
 servicesfx_cont1
 
-     ldy #1 ; check to see if they're changing the priority/frame countdown
+     ldy #1 ; check to see if they're changing the frame countdown
      lda (inttemp5),y
-     cmp #$20
+     cmp #$10
      bne servicesfx_cont1a
-     iny
-     lda (inttemp5),y
-     sta sfx1priority,x
-     iny
+     ldy #2
      lda (inttemp5),y
      sta sfx1frames,x ; change the frame countdown
      lda #0