This might be the first time I've heard of an N64 that *didn't* work perfectly. Seriously. In all the dozens of consoles, I've never seen a broken N64. I've seen them beat all to hell, with pennies rattling around inside of them and the reset button jammed down, glued there with spilled coke. I've seen one with the housing completely smashed. But I've never seen one that wouldn't work.
Beyond a bad solder joint on the port, or something conductive shorting the audio output, I wouldn't bother trying to fix it. Just find a cosmetically damaged N64 and swap the board.
-Ian
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