Marshall crackling was driving me nuts

[drewl]

had a 2203 that was crackling intermittantly.
Narrowed it down to V2, and it seems the the resistor lead that runs V2a pin 1 to the input grid V2b pin 7 was rubbing up against the center post, just barely touching it so sometimes it would make contact, then not, causing an annoying crackling.

Just thought i'd pass it on if any of you come across this and didn't know already.