Sony receiver stereo problem

[Alibi]

Have a Sony STR V4. After about 30 minutes listening to FM stereo, the right channel goes almost completely out. Lots of static.

The stereo light remains on and both channels work fine in mono mode. The problem does seem to go away after moving up and down the dial several times, then may or may not reappear.

Any help appreciated!

 

[Punker X]

Has all the switches and controls been cleaned with Deoxit? Many threads on AK on how to do this.

 

[Alibi]

All pots, switches recently cleaned and the tuner was aligned recently as well. This problem is like it's on a timer. About 30 minutes into listening, the right channel (in FM stereo only) becomes distorted and muted. The STEREO light remains on. Switching into MONO the right channel comes back, so it doesn't seem amplifier related.

I know it's a long shot. Thanks, guys, in advance

 

[N8Nagel]

Selector switch cooked and falling apart? Had this happen to me on Luxman receiver recently.

 

[Alibi]

Selector switch cooked and falling apart?

Indeed it is the stereo/mono switch. Shot some CRC in there and moved it 50 times. This cured the problem for a few minutes. It either needs replacing or more cleaning. I figured it was something on the tuner board heating up. Never figured a switch would malfunction after a period of time like that. That being said, I don't have any other inputs to try with this thing so that might have narrowed it down earlier.

I'm impressed. N8Nagel, PunkerX, thanks!

 

[N8Nagel]

That was just a guess, but it turns out it was correct... I just went through this with my Lux R-1120 which has been out of service for over a year after the second time that a channel completely dropped out. Previous tech reflowed a bunch of stuff in the preamp and it magically came back, then the problem came back for good, turns out the source selector had actually started to fall apart and he had to glue it back together. When stuff gets to A Certain Age, EVERYTHING is suspect it seems.

This is the same intermittent problem that got me to purchase the thing for cheap in the first place, but it took about 3 years for it to declare itself permanently enough to become evident what the issue was... every time before you'd uncase it (a project in itself) and then fiddle with some stuff and you'd think you'd fixed it but you really hadn't...