Hi:

I'm aware of the hot/cold technique, and will try it if I can find
some freon in a can (Don't think you can buy it anymore).

I don't think it is a heating problem, as it happens immediately
even when the radio is cold.

No joy on the physical inspection, either - this one looks brand
new inside.

I do suspect a bad cap - but which one? Wish I had a schematic.

BTW - I have been building & fixing radios for 40 years.

Thanks for the suggestions.

Dave Johnson