E6d-73 - ghost in machine: 4' drawbar "follows" the 8' drawbar????

[wnmeinc]

Okay so my 6d is still practically brand new. I'm too familiar with drawbar fader problems from my woes with an 5d, but I've got a few extra faders laying around I can easily solder in if necessary...but that's not the usual problem today. My 4' drawbar isn't responding to the fader being moved. Normally I'd assume the fader died, but when I move the 8' drawbar up, the 4' "creeps" up until its 1 less than the 8' setting, or "creeps" down to 1 more than the 8' setting when moving the 8' down.
I cracked it open...no shorts, burns, hair or debris anywhere. Clea as a whistle. What would cause the 4' to "slave" to the 8' like that???

[maxpiano]

Did you check also the flat cables are well connected on either side (unplug/clean socket contacts/replug) + apply some contact cleaning on the board near the 2 faders soldering points?

PS: welcome to NUF...