TMNT 1 - No sound

[ArcadeDunce]

Am I ---steaming pile of meadow muffin--- out of luck?  It started smoking once..... that black piece on the top right by the Jamma Connector.  Maybe it blew something out?  I'm curious as to how easy it is to diagnose, because it works perfectly otherwise...Perfect picture, controls still work, just no sound and I'd hate to trash it.

[bkenobi]

First step is to examine the board and see what's obviously burnt.  Anything that's charred will likely need to be replaced, but you may have other components that are dead that won't appear to be damaged. 

I would suggest taking/sending it to someone who does this if you want it done right.  There are people on this board who can help fix it if it's repairable.

[anyeyeover]

There is a resistor array (black rectangular component) that controls some of the sounds.  My board wouldn't do the character voices and some cut scene sounds and that resistor array was physically damaged.  Found a replacement and it fixed the problem.  My theme music has never worked though (and yes, attract mode is on), so the sound isn't 100%.  I would inspect the board and see what got smoked.

[MonMotha]

The big black thing with the heatsink at the top right near JAMMA is the audio amp.  If it's smoked, it's probably bad, but may have just overheated.  I've noted that the heatsink attachment method can apply a lot of force to the board and sometimes cracks things at the pins for the amp.  Inspect to see if that happened.  You may be able to just reflow some solder joints, but if there was smoke, then it's probably broken.

IIRC, the part used on that board is EOL, but somebody may have some left, or there may be a drop-in replacement.