Hi,
My Popeye has a sound problem: sometimes the sound goes VERY LOUD at the start of a ball, with the next ball it goes back to normal volume. It can also take 2-3 balls to go back to normal. I can turn the volume down using the buttons, but with just one push of the button it immediately goes back to it's original setting (so no need to push multiple times). Also sometimes during gameplay, the background music is gone and comes back at the next ball. This also often happens during the bonus animation, then suddenly the music drops.

Other than this, the sound is good (loud, clear, no hum/buzz or whatever)

What I've done so far:
Replaced C36 + C44 +C22 (tant capa's)
Replaced U27 + U28 (TDA2030A amp chip)
Replaced C20 + C21 (big capa's)
Replaced U21 +U29 (TL084 op amp)
Resoldered I/O pins
Took out all EPROMS and carefully cleaned their pins and put back
Exchanged flat cable with working one (other pinball) --> no difference

I'm not very technical, but it almost feels like some signals are not coming through properly?? I read something about a "DAC for the DSP" that can cause problems, but not sure what that means.

Hope someone can help me to get on the right track,
Barry