Interesting. I think the booster board is there to drive a higher
wattage STK module or whatever it uses. Its a simple amp &
cap coupled so a snap to eliminate.
If the VC goes to ground on one end be sure it is ! A cracked pot
could do it to.
Last thing you probably know. If you plug a phono with a ceramic cartridge
into the magnetic cart input it will blast you out of the house. This
was a common problem when someone added a TT to a stereo & got the wrong one.
73 Zeno
LFOD !