High-pitch noise in old tube amp (oscillation?)

[slidincharlie (Carlo P)]

I have restored a Silvertone 1472 that I bought about one year ago. It was scratchy, very noisy and in need of a general overhaul. I did a cap job, replaced most tone and coupling caps (leaky) and a couple drifted resistors.
Now it has a noise issue: no buzz or hum, just a high-pitch noise that follows the volume pot setting. It's almost like the noise from an off-tune AM radio. I'm not sure if it's oscillation, because the noise is there at any volume and tone setting (louder if I turn the volume up).
What could it be?
I attach a picture of the chassis, in case you guys spot anything badly done.

[52 Bill]

...just a high-pitch noise that follows the volume pot setting. It's almost like the noise from an off-tune AM radio. I'm not sure if it's oscillation, because the noise is there at any volume and tone setting (louder if I turn the volume up).

Does it happen on both channels or just one?

[slidincharlie (Carlo P)]

S**t! I left it at the rehearsal garage.
I can take it next Tuesday.
Please hold on until then...
Thanks, Bill.

[tubeswell]

Maybe a cold solder joint in the work you just recently did? Maybe re-flow all the joints with a bit of resin-core leaded solder.