I have been having an issue with my Yamaha RX-V573 receiver for some time now. It has developed a problem of the right channel playing little to no volume when the receiver is first turned on until the volume is turned up. My receiver is set to start at -50.0dB and at this level the left channel is very noticeably louder and it sounds as if the right is dead silent. As I turn the volume up to -20.0dB I can hear the sound shift back into the centre as the right channel starts playing at a normal volume now. After I have turned the receiver up, I am able to lower the volume back down to -50.0dB where both channels play at their appropriate volumes but if the content is very quiet or nothing is playing the right channel can cut out again and I have to turn the volume back up.
Now, I have done some trouble shooting myself to try and isolate the problem. I have switched the left and right speaker outputs and the problem still persists on the right output channel from the receiver so the speaker wire and the speakers aren't to blame. I am currently using optical as my source from a PC however I have used HDMI and AirPlay, all presenting the same issues. The issue is prevalent on both Zone A and Zone B of my receiver in the right channel of these. I have also blown out dust from inside the receiver with some compressed air and I desoldered and switched the relay from Zone A (RY203) with the relay from Zone B (RY202) as relays seem to be the culprit found on other posts however this did not fix the issue. The relays themselves are sealed so I am unable to clean the contacts out with de-oxit but seeing as they are completely sealed and this is a 2012 model it seems unlikely that they are to blame.
As a temporary fix, I am able to plug my right speaker into the Surround Right output of the receiver and put the receiver into 7 channel stereo mode (This is the DSP mode, not true 7 channel audio). This takes a stereo source and plays the same input on the surround channels. Interestingly this channel works perfectly and suffers no volume issues even though it is just a stereo source being duplicated onto the surround channels.
If anyone has any inklings or ideas about what the issue may be it would be greatly appreciated as this is a very befuddling issue!
Receiver: Yamaha Rx-V573
Speakers: Wharfedale Diamond 8.3
Source: Windows PC onboard soundcard via optical