Remote no longer works for volume control
Guys, I might have accidentally found the problem because the fix worked for me :). I have the RX-V995 and for the last 2+years or so, I had resorted to getting up and using the knob manually for volume control. System will show 'voluem up/down' in the display, but the knob didn't rotate. Same problem as yours.
I was getting ready to buy the service manual, find the knob motor which I thought was the main culprict and replace with a new one.
So I took out the top cover (just a few screws), the front face-plate (again just a few screws. The inner details were all visible. The volume knob circuit board was vertically placed. They were all covered in a good layer of dust. I got my Dyson vacuum cleaner and gently and carefully tried to **** up all the dust that had settled down. With soft front brushes, I agitated the dust I couldn't reach with dyson wand direclty, once dust were loose, dyson did a great job even with picking up those last dust pieces.
I couldn't succeed in taking apart the volume knob circuit board, as I was still awaiting for the service manual. I put all the covers back on and guess what? I used my remote and the knob was moving again. Responding very well, the knob made the full turn, when I was on the remote. It has been working perfectly for the last few days now.
I think I know what was happening. Teh top of the RX-V (and I am sure many Yamaha receivers) are very porous to allow for good heat dissipation. Over time, this allows a large amount of dust to collect on top of the parts. Most parts are electronic (not mechanical) and hence don't get affected by the dust. But the few mechanical parts might have adverse affect if dust settles down in between the rotating mechanisms.
My volume knob had stopped responding to remote command, very slowly. Initially it worked a little, missed a little, then it missed a lot and eventually it didn't rotate. That proves the theory to some extent that if the motor had completely failed, it would stop working from the get-go, not intermittently. Dust build-up provided intermittent contact between the parts and hence the response was intermittent.
The dyson vacuum did a great job in pulling out those fine dust from such parts and amazingly, things are looking very good at present. Honestly, I hadn't the slightest hope that vacuuming would fix the problem. I had vacuumed to make it easy for me to work on the parts :).
So, it doesn't hurt at all to just give it a try. Do open the covers so that you can reach closer to the real boards and parts.
Good luck and let us know!!!
PN from San Jose, CA