Princeton Reverb build Volume issue??

[g1]

If there's no filter properly wired to the preamp high voltage node then signal from the first triode won't be decoupled in the power supply.

Even poor grounding of the 'node D' filter cap could probably cause this issue. But a defective new cap there is also a possibility.
Try clipping another new cap across it.

[Govmnt_Lacky]

Even poor grounding of the 'node D' filter cap could probably cause this issue. But a defective new cap there is also a possibility.
Try clipping another new cap across it.

The circuit uses a 40/20/20/20 cap. I verified each section was +/-2uF within tolerance at each node. I will look it all over again and report back.