Something isn't right with the amp. The 15 amp circuit breaker would trip first if their wasn't enough current to handle the amp. It isn't the circuit wiring. However, there may be a voltage sagging problem with the amp pluged into that particular wiring. if the wiring isn't adequate, at turn on, with too much amp draw, the voltage drop may be substantial enough to turn off the amp based on low voltage protection in the amp. So AudioLabrith may be correct to a point. It isn't the rating of the circuit breaker, but it may be the actual wiring itself. Take the amp to another place with a dedicated 20 amp ciruit (say the dealer where you bought it) and plug it into a 20 amp circuit with 10 gauge wiring and see if it stays on. No amp should trip off if speakers aren't connected.
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