The board was in good state but it gave a solid black screen.Upon a quick inspection I found the reason, the 'TC0070RGB' module was missing , probably someone took it (removed in a neat way I must admit) in order to fix another board :
Not having a spare I opted to use a reproduction of mine :
The board booted up and game was fully playabe but sound was distorted and corrupted :
Using an audio probe I figured out that sound came out clean from the YM3014 DAC but then it reached the input of the main amplifier (Fuitsu MB3731) already corrupted.In the middle there are two OP-AMPs : a dual one uPC4556 and a quad TL074 :
Usually when I troubleshoot analog sound issue I'm not one for subtlety hence I replaced the two OP-AMPs straight away :
This restored a correct sound.Repair accomplished and another board added to my growing collection.
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