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SONY DA50ES - No output - Right Front A/B Channel

I have a Sony DA50ES receiver that recently quit working correctly. I have no output from the Right Front A/B channel. I have verified the speaker and wiring are good by connecting to the other channels while running the "test tone" and also trying each source in stereo and surround sound. I want to believe that it is a bad fuse but I have checked all of the visible ones and they are all ok. Can anyone help me with this? Anyone have a similar issue and successfully fixed it?