Help: right channel not working on Yamaha rx-v3000

Ihcho,
If it works for the rca input and plays at the speakers, that eliminates a blown output channel, which is good. My guess is that it may be a bad digital cable. Some, especially early, digital cables were fiber optic and contained glass internally. These types of cables cannot be bent or crimped since it will break the glass inside.
This is easy enough to check by just swapping out your cable for another.
If that doesn't work, you may need to bring it in for service and have them check it out internally.Hope it's just a cable, good luck.

Maybe the dac is ready for a retire.

Have you try unplug it from the AC outlet for a minute to reset the processor?

Thanks for response.
Looks like DAC parts are dead.
I ordered digital to 5.1 analog signal converter. Hope it would work, even with sound quality degrade.

The digital to 5.1 converter, with the 6.1 channel input from the receiver, worked just fine. It cost me $60 for the converter and I guess I can save the Yamaha receiver for a while.