Unplug all the speaker wires first, then unplug the unit from the wall for at least 24 hours, The plug back in without the speaker wires or anything else plugged in. Then see if it goes to the protection mode. If it does not, plug in each speaker at a time, and see if any speaker, when hooked up, makes the receiver shut down. If it does shut down, My friend, I'm afraid you will need to take this unit into a repair shop, OR get a new unit. Good Luck
The problem might be caused by two major circumstances. 1)Touching wires 2)Overheating. I suggest you unplug all wires connected to the amp then turn on the amp. If it gets turned on then we know that the problem is that you have touching wires. If there is a short circuit somewhere, get rid of it. The ventilation is another important issue that you have to pay attention. It simply causes overheating.
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