Hey Amp Gurus! Please help, I'm kinda freaked out: I bought a brand new JTM style build with 2 6V6's / 20 watt - the guy is a new builder. It's a basic single channel - Gain/Master TMBP, with 2 inputs, and Fx Loop Option. Tone is pretty nice, but…. *Please let me know if this normal for a JTM45 isn preamp: - The Treble Control adds LOTS of bass when turning CCW from 2-0, and from 5-10 it's really thin and seems to suck gain also. - Presence Control - not working at all? No real change turning 0-10 The builder says it is due to the very high amount of negative feedback in the circuit, *ALSO on first play, a bunch of red flags went up (have not discussed this part with the builder yet) - ANY HINTS or THEORIES on this would be very much appreciated: - Lots of hum (base level - with controls zeroed, guitar plugged in or not), - Very loud hum/buzz on idle with all controls at noon - goes away mostly when guitar plugged in the Clean Input, but no noise change at all when guitar plugged in Crunch Input - - Also, if you touch the speaker cable's metal sleeve, the noise changes / gets louder bassier! - with or without guitar plugged in… Bad grounding issues? Stray high voltage maybe?? Many thanks in advance!!!!