Check to see if the antenna is firmly connected and not making contact with the receiver chassis or other inputs/outputs.
Try disconnecting all of your speakers, and then turn on you unit. If you have a defective speaker, or a short in your wires, your unit will go into protect mode. If your unit seems ok with the speakers disconnected, then turn unit off, hook up one of the speaker leads and try it. This way you can isolate the problem.......
This can be shorted output transistors (common) or a defective voltage amplifier IC. WIthout taking measurements inside, there is no way for me to make that determination. In any case, this should be a relatively simple repair for a shop that repairs audio gear. Expect a parts cost in the $25-$40 range.
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