if you are not willing to open it up and troubleshoot, we're done. Buy new receiver.
if you don't know transformer vs rectifier vs transistor, we're also done.
As Giz says, ez thing to test is the power supply, then most likely one or more of the power transistors (the ones attached to big heatsinks) are bad, and for that u need a multimeter and know how to test a transistor. Another ez thing to do is to open it up and inspect for dark spots, this is where burnt components are.
Solution: FREE. Explanation: I will have to charge$ you.