Hello friend Walterenduro, if the amplifier has the original speakers, you would have to measure the impedance of them "8 ohms" in each one, if the impedance is below what was indicated that would be a reason or if you change the speakers "speakers" in bulk wattage that would be another cause or that has added more speakers to the amplifier, if the speakers have piezoelectric twitter and are overheated or short that would be another reason. An easy way to counteract the amplifier's overheating is to adapt a "fan" heat extractor so that the amplifier works without any risk of overheating. Greetings from Valledupar Colombia.