Yamaha RX-V590 faults

[MrCurly]

Hi All,

We recently moved house, during which all our stereo gear was carefully packed and transported in the back of our car, as it had hardly been used over the past two years i can not be sure i am looking at an existing fault - or if it was caused in transit.

Anyway... since setting up my stereo equipment i have noticed i am getting intermittent noise on one channel (I have a pair of Polks connected to the 'A' main channel as front speakers at the moment - as per its usual config).

It is particularly noticeable when there is no music being played and the volume is cranked up a little, sounding like random rf static with the occassional pop. Once a CD is playing it is barely noticeable, leading me to wonder if this was a problem for quite a while..

The other problem, which was pretty weird, was when switching from Radio to CD on the front panel buttons the amp did not immediately switch the input, continuing to stay on AM. This is a secondary problem, as a power reset seemed to fix it, just unusual that it should become a problem after moving the unit.

Has anybody experienced similar problems? or can suggest any component that may be the culprit, or where to start debugging the fault?

I don't have a cct diagram or workshop manual for the RX-V590, and would really appreciate it if somebody could provide one. I do not have a scope, but do have a multimeter, and most of the kit required for board level electronic repairs.

I appreciate any help with this! Can't really afford to send it off to a hifi techo.

BTW - This unit was cooked about 14 years ago after a lightning generated brown out, it was fixed under insurance then, and was in the workshop for about 5 months getting practically every internal component replaced.. has run flawlessly since - well until recently!