Try unplugging the unit for 60 minutes, then plug back in and try it again. This will reset the processor and hopefully the unit will operate normally. Check all the speaker wiring for shorts, make sure they're also not touching the chassis of the receiver, or are not otherwise pinched or frayed. If all looks well, try disconnecting all the speakers and cycle the power off, then on again. If you have "protect" on the screen, OR the unit shuts down, or fails to power up with no load connected, then the unit has a bad output transistor, or capacitor and is in need of service. I can send you the contact info for a Service Center near you if you'd like.
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