Are you sure that the Main power and the ground is connected and you are gettting this switch on of the amp. If so there is a shorting inthe standby/ relay switch on circuit. You will have to open the amp and check for any burnouts. since the power is on I presume that if the set is new , some one had wrongly connected the amp damaging the circuit. It has to be probed if this proves expensive and beyond the scope of this advice. If you notice any trigg transistors, relay faulty replace other wise you need expert help. Hope you find this helpful. Good day