General Electric A-64 advice needed.....low volume

[Kamakiri]

Got this radio in a very sorry state.....the underside of the chassis was PACKED SOLID with a rodent nest, tubes missing, etc, but the cabinet was nice, and not deteriorated, as you'd expect something like this to be.

But getting to the issue, I've recapped the set (this thing has an ungodly amount of capacitors), but it's exhibiting an odd condition.....I get low volume no matter how high I turn it up, but I can flick the radio on and off quickly and for about half a second when I flip it on, the audio comes up VERY strong and loud. I figure that it's got to be something that someone will recognize immediately and something that I might never find