Don’t think it’s the dip switches. Do you get the start up tune when you power up the game?

You might want to try changing the PIA at U7. I think the signal for the sound test from the coin door goes to the PIA, while the test button on the board doesn’t. Sometimes a port can be bad and it will still pass the self test at startup.

The mpu signals are not all getting to the 6803 sound cpu. Usually it’s the connectors or the PIA. Slight chance it’s the cpu. When you press the test button on the Vidiot, do you get the sound(like a ray gun). ? Then two flashes, not three.

Maybe one of the communication chips. I’ll look at the schematic tomorrow and get back.

I think the switch data inputs to the 6803 on pins 9-12. Step 1: Best to use a logic probe to see if there is activity on these pins as switches are closed.

I didn't realize the switch hits made sounds. Thought you said there was no sound on switch hits. Did you say the sound test doesn't work from the coin door switch? If it doesn't the mpu isn't communicating to with the 6803.

There is a switch matrix on the Vidiot for those sounds. Seems like that is working. I think the sound test and other communication from the mpu come directly through one of the communication chips, maybe U6. I gotta look at the schematic.