SounStream LW4.620 output issue

Hello everyone,

I'm working on a SoundStream LW4.620 that has DC on the output without a signal and a square wave with a signal.

Everything checks out both in and out of the circuit.

Someone has worked on it before.

So far, I’ve found some disconnected jumpers and a failed diode. I’ve replaced all of them, but the issue persists.

All four channels have the same fault.

Does anybody know or have experience with this issue?

Any help would be greatly appreciated. 🙏

Signal on the base of the output transistors before clipping⬇️
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