Stereo operation question
 

I have question for our stereo buffs: My now old Yamaha DSP A1 amp is working strangely. Some of the speakers stopped working. I checked all the cables, switched the speakers around, checked the inputs, sprayed Deoxit into the balance switch, checked the fuses and relays (sprayed them too) and nothing changed. I am trying to avoid taking it in to a shop as it is heavy, 60 pounds) Then this morning i turned it on, still nothing. I cranked it up half way (that is a LOT on this thing) and suddenly all the speakers came back, and they work on any volume setting. Any ideas why this could happen? Thanks

Could it be as simple as the volume/potentiometer is needing replacement?
Work that knob back and forth a dozen times or so.

I am no expert..just an idea.

My Marantz receiver has a muting option that doesn't completely shut off the sound, maybe something like that it getting stuck on somehow?

There are probably output relays that protect the output transistors. Sometimes they stick...

If the flux capacitors are old, then they should be replaced.

Thanks guys, I have some 100% Deoxit coming, I will take the cover off again a give all the usual suspects a bath. I changed out the flux capacitors last year, hard to find these days with the chip shortages.. I found the mute control, it is off. Thanks