I recall Phil posted a photo of Barkhausen oscillation recently and it appears as a narrow squiggly vertical line. I did try different tubes and it had no effect.
I've also noticed fine tuning does have quite an effect on it as Eric mentioned earlier. I'm going to hold off on fooling with that issue and the buzzy audio until I do an alignment. Between replacing so many caps, resistors and tubes I figure it's got to be off.
Here's about when the arcing sound is worse as power up
and at power down
I get a sense there's built up energy looking for somewhere to go. I'm also starting to wonder if the sound is actually coming from the speakers and not arcing at all.