Need help with Wondermega Audio.

[Danexmurder]

I’m having an audio issue with a Wondermega that I have had no luck tracking down. I could use some help as I seem to be at the limit of my diagnostic powers.

Audio on the main board seems fine. I haven’t noticed any issues with cartridge based games.

It gets tricky on the CD side. When you boot up the Wondermega there is no Bios audio. I put in final Fight CD and the CD audio is working but no sound effects play. So you get music but just occasional static sounding noise when you punch/kick etc.

There is very little documentation out there on this console. Nothing looks physically bad. I recently replaced all of the caps.

Any pointers on what/where to test would be very appreciated.