Komet 60 help

[EstimatedAntelope]

So I got a call from the friend I built the Komet 60 for...when it left my hands it sounded loud and clean. He started noticing hum and buzz, etc....oh no.

I get the amp in and it's making no audible guitar noises and just loud hum and buzz. I first tried a bunch of tubes. I got a combo that sounded good and fixed some of the issue, but it's still there. I opened up the amp and decided some wiring could get cleaned up and I touched up some solder joints just to make myself feel good.

Here's where I'm at::::

The amp has a loud 120hz hum (confirmed freq. on my scope). When I pull V1 it disappears. I tried a million tubes in this position and various tubes do affect the severity of the hum. I thought I found the perfect combo 2 days ago and when I fired the amp up yesterday the hum was back...

Volume controls the hum entirely. Volume down, no hum. Volume up it gets louder.

I took it upon myself...again...to basically rewire everything around V1 and V2 to shorten leads, clean up any solder. I did note while poking around the amp that the .022 caps for the tone controls were noisy when I tapped on them...could they be leaking causing an issue? Would this cause issues upstream at the volume control?

I'm about out of ideas at this point besides tearing it down and rebuilding it again but that feels like insanity.

[ViperDoc]

Look for bad or missing grounds, or ground loops, and any problems with the power supply.

[EstimatedAntelope]

Look for bad or missing grounds, or ground loops, and any problems with the power supply.

So now something weird is happening. I got the signal cleaned up. Just sits with barely any noise on the scope when it's on. But...when I turned my signal generator on (1kHz @ 250mV), the amp runs fine until I start increasing the volume and then at about 80+% it will blow a fuse.

I'm thinking it's a tube at this point that is shorting out under higher load?