MTX Thunder 81000D Problem

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Hi I have a MTX thunder 81000D thier is a high pitched whining sound comming form the transformer but I was getting sound out of the board and when I pushed on the board it would go away.

With the whining sound the output signal was not a normal subwoofer signal.

Once I pushed on the board the signal was back to normal so I figured it was bad solder connections.

I resoldered the amp, I still have the same problem then somthing smoked but since im using a variable psu it protected the amp right away.

I started trouble shooting but without a schemtaic its hard.

I replaced 2 SMT's q264 and q263. I still have the same problem.

Im getting -70 and +70 volts from the fets. LED238 is on.

I checked chip TL494C im getting a sawtooth signal and the square wave signal to the fets is not much of a square wave it is a cross between a sine and a square.

Anyway Im kinda stuck without a schmatic at this point. So any help would be great.
 
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