That is the dual amp version of Star Force - DO NOT use the PCB junkie adapter on that without modifying the adapter. You need to lift pins 16/T from that adapter, it is pushing 5v down those traces which is fine for a bunch of other Tekhan games, but not the dual amp version of Star Force.
When you were testing the heatsink was probably as hot as the space shuttle, and the amp that is tied to 16/T will be pooched. I think it is the one that is closer to the side of the board. The second volume pot may not do anything either if that AMP is dead.
Here is a thread I added to regarding this board.
OK, Have a Tehkan Star Force here for repair and thought I'd just document where it is so far. It has been a royal bitch! Symptom: Dead. Stuck in watchdog. Audio amplifier heatsink gets red hot. The audio issue is interesting because this particular board has 2 audio amps and double the audio...
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