Ok, so we finished sorting a Simpsons Party recently and tested it for a few weeks,

we replaced the top board as it had battery leaked, we took a chance on the lower board thinking it wasn't too bad.

We had sound perfectly for a while (few weeks) on the Rottendog board replacement. The machine was moved to customers premises and after a week we now have corrupt sound.

We had the speakers out and cleaned the grills.

NOTHING is coming out of the top two speakers, but the BASS speaker is making this noise.

What is going on?

could do with some thoughts

Thanks for the words, I been to see the machine myself. I did many tests, voltages looked acceptable, amps seemed to be ok, its crackly audio at full volume out of speakers.
I swapped Processors, BTSM chip, I can see negative and positive voltages at the amp. Lifted the four chips for sounds. I could not find it. The supply voltaes were a touch over 12volt going into the board.
PinWiki is hinting TDA chip, anyone know if Rottendog game boards struggle with their TDA chips?

I just wanted to update this as - The problem was the TDA D/A chip near the amps on the Rottendog board.

However i got another problem now that I start in a new thread.