Oh man, you're giving me flashbacks. I lived in a high rise apartment building when I was in high school in the 70s. I'm remembering the fallout shelter signs in the basement.
Yeah exactly like this!
It is a new build indeed.
I did clean the tube pins but that didn't help. Manipulating the tubes has no effect. Only thing I think affects is when I poke around the red wires on the underside, but there is not 1 place that makes it any more than the other. Its like the whole red path makes it. Or it just happens to crackle at that specific time.
soldered speedball again and voltages improved a bit:
Small board:
OA 70
IA 191
B-A/B 0
IB 190
OB 69
Big board:
OA 106
OB 106
G 0
B+ 193
Edit:/
MAN this amp is baiting me so hard. I was doing reflowing and whatnot, turned the amp over added the tubes and did some more chopstick testing. I hear the same freaking sound again and then I see I forgot to add solder to the connection from hp jack to 6L, I poke the connection and when i press the wire from the middle down with my finger the amp goes dead silent. The quietest I have ever heard it. Im like this is it. The 6L end of the terminal had the wire just go straight to the hole and soldered, so there was no proper physical connection. I went and bent the wire over the terminal and pressed tight, soldered and I was SO HOPEFUL. I power the amp and everything is the same as before. Even the voltages went up the old where they are a bit higher. What are the changes that after I have redone all circuits, swapped wires etc. etc. there would still be a cold solder or a bad wire after the chopstick test has no effect, and I can sometimes make the sound go away with wiggling the small tube, but so I can with wiggling random wires from underneath.
Is there any chance that the 6as7g could be the culprit?