Hello all, I am fixing a punch 4040 dsm amplifier I got for free that had a shorted output transistor that caused the left rear channel to output rail DC. I have replaced all the buz11 output transistors and it solved the DC problem, but now the audio in that channel is scratchy and distorted at all volume levels. I've tried playing with the gain, treble, bass, phase, and input switches to see if any of those were causing it (like if they need a touch of deoxit for example), but no go.
What causes this and what parts would I need to replace next?
What causes this and what parts would I need to replace next?