Demolition Derby has no sound, any ideas?

[Bullwinkle]

I have a Midway Demolition Derby 2player upright that seems to be touchy. Prior to moving to basement, we had sound, then we moved it.. no sound. We thought we had figured it out and got sound again...then moved it to my final resting place in my gameroom and we're back to no sound.

The volume pot tests OK, but it definitely appears to be something loose, but cant find it. Any suggestions? the 3 board pcb stack has an MCR II Sound I/O Board w/ Panning on top which appears to hook to a cheapsqueak and then to an MCR III dual audio amp (although not sure why dual) and then out to the speaker. the limited manual I have says there should be an MCR II audio amp, so the pinouts in that book don't even match what I have.

That being said, it has worked in the past..just not sure what or why it's not working now. I've checked all the connections.

[Oryk Zinyo]

Have you checked the boards for cold solder joints? Especially around the connector harness pins...

[Bullwinkle]

Originally Posted by Oryk Zinyo

Have you checked the boards for cold solder joints? Especially around the connector harness pins...

I did reflow solder on the MCRIII dual amp board. I probably should do the same to the cheapsqueak and the main audio board in the stack. Good point.