| The first thing I would do is pull the tubes that are used for the Lead only and, with something small enough, push in the edges of the individual sockets in the tube socket so that the tube pins will make tight connections. If that didn't fix the problem, did you swap that tube with a tube that is used in the clean channel, to verify it's not that tube? Next after that I would be suspicious of the switching circuit, can't remember if it's Vactrols or relays. |