does the repair manual have an electrical diagram? that has a feed back style power supply, you may just have an optoisolator out. that would tell your power supply not to power your sound board.
I know how dang frustrating it is to pay $600+ for a tv and then have it crap the bed.
remember any little hole in the top of the caps, or anything leaking out, it could even look like the dielectric glue stuff, and that cap is not gonna perform to spec.
half a volt drop in the output to your sound board will make the feedback loop shut down.
I'd like to think I'm the guy they are talkin about when they say, "he could F%^& up a cannon ball in a plowed field."
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