Sony cs-500 weird volume / radio reception isssue

[Madmox]

Picked up this unit on the weekend.
Decent shape, with the usual crackling slide volume controls.
Pulled it apart, very clean inside. Used spray contact cleaner on the volume and eq controls, record bar and tuner. Blew out the excess with canned air and finished up with deoxit. Put it back together and everything sounded nice an clean. At first. After about 5-10 minutes, the volume drops and the I lose the lower end of the FM band. However, if I hit play on the tape deck, everything sounds fine. Radio comes back and the sound is bang on. Weird. Unplug for a little while and it resets and starts the volume drop thing again.
I thought it was still a little damp from the cleaner, but, it's been over 24 hours now. Any suggestions?

 

[hopey]

Common problem with record bar. Because of full auto stop the radio runs through contacts on the record bar. Try pressing Play and record 50 times.

 

[Madmox]

Thanks hopey, that helped.
Another thing I noticed though, FM stereo light only comes on when tape deck is playing. For now, just having the deck, in paused playback, fixes the volume and stereo issue completely. Still sound like a record bar issue? Unfortunately, the record bar is almost totally blocked, on both ends. Hard to get in there to clean it.

 

[hopey]

You can spray with contact cleaner or alcohol. As the contacts are affected by corrosion and exposure to moisture over the years the only way to fix it is to remove from PCB and disassemble and clean by hand.