If it does move with the preamp output swap you could then go further.
Open up the preamp( powered down of course) and swap the tubes themselves L and R.
While in there you might possibly find one tube was loose in its socket.
Anything is possible but I would definitely start at the Modwright if it was myself.
Good luck.
Open up the preamp( powered down of course) and swap the tubes themselves L and R.
While in there you might possibly find one tube was loose in its socket.
Anything is possible but I would definitely start at the Modwright if it was myself.
Good luck.