I have a Sunn Sx-6350 that I have been working on for months. Replaced all the outputs,drivers,transistors on board,power caps and a bunch of other stuff. Power supply works fine. Can power up with the old light bulb trick and everything works fine, but as soon as I plug it in the wall it frys the internal fuses. Somthig on the board is allowing to much current to flow but I can't find it. HELP