Have a Sony STR AV-920 Receiver. Recently when its playing (CD or Tuner) the volume will go full blast. Any idea what internal component may be causing this? I would like to repair it myself, rather than replace it.
The volume pot seems fine, this isn't something I can recreate. It is just on for a while and then - boom - full volume. The pot doesn't make any crackle sound and the volume increases smoothly when I turn it. It just this darn intermittent thing. Thanks.
Most contemporary receivers like your Sony have the potentiometer control on the master control chip, a large scale IC that controls most of the functions of the pre amp. (I know that's a lot of "controls" in one sentence but I didn't design the chip, someone else made me do it.) There could possibly be a small semiconductor that is not feeding the correct information to the chip or even an error at the remote sensor, but this isn't the sort of problem most people can repair themself. Find a qualified tech and ask for an estimate of the repair cost before OK'ing the job.
If you have the thing opened already, then sek any 'service mount' ic's(those which push in). gently rock and push them back into place. Seat firmly, but gently. Run a toothbrush across all of the pins of the ic.
It may seem like'lather,rinse,repeat' but it might help.