is there an output relay that is stuck on? some amps have a relay on the speaker output to prevent turn on thumps from reaching the speaker as well as protection, it could be stuck
No relays, here is what I see, there are 2) TL712 comparator
Fallow by 2) IR2010 that drives 8 IRFP4768
Audio mosfets, each IR2010 is driving 4 mosfets.