Yes, as Tom perceptively pointed out, past experience here has taught us that the first thing to check when a receiver shuts down is a short in the wiring. Although there are occasions where overheating has required a shutdown because of playing too long at too loud a level for the capabilities of the receiver, all too often it's imagined that there's an inherent inadequacy in the receiver, particularly if the speakers happen to carry a 4 ohm rating.

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Enjoy the music, not the equipment.