Yamaha AV Receiver (DSP-A1092) don't work properly

Yamaha AV Receiver (DSP-A1092) don't work properly

Hi, I have a Yamaha AV Receiver, DSP-A1092 and I'm not able to find exactly what is the problem. The outputs are not working, except for the front effect (R and L). I know could be the logic board, the amp or relays.

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