So Kickman appeared to be working OK, but I could only hear sound from one speaker. I put the game in test mode and Channels 1-3 were producing sound, but channels 4-6 were dead. Probing the two PSGs showed that each one was received its enable signal. The buffer at C6 showed that all channels were good as well. When I put my scope to the inputs of the opamp at D3, pin 1 input would cause speaker hiss when probed but pin 2 input produced no sound. I replaced this LM3900 opamp and all channels worked again.
Success was short lived as an hour later channels 1-3 died. I pulled the game out, got out the scope, and probed the buffer at C6 again. This time, all signals from the PSG(AY 8910) at F7 were absent. I swapped the chip at F7 and (for now) Kickman produces all of its sounds again!!!
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