If the noise seems to be coming directly from a motor it could be a problem with the motor. I think there's capacitor in the wire path to the motors that can drift out of synch somehow. Mike at VPI told me something about that. When you reverse the wiring it could introduce coginess to that motor. In that case, I'm sure VPI would send you a new motor. If the motor seems to be the source I would conact Mike. He would understand it a lot better than I do.
I would try to make sure that it's not drive belt noise by moving the motor assembly away from the platter. If your noise stops, try lighter conact of the drive belt with the platter and this will decrease or stop with time. Also you might try removing the belts from the motors and watching them run freely to see if one is more jerky than the other. Mine is running smoothly with barely notable motor and contact noise.
I hope this helps. I don't consider myself an expert on this, or anything really, but this is what knowledge I've gained from my experience so far.
I would try to make sure that it's not drive belt noise by moving the motor assembly away from the platter. If your noise stops, try lighter conact of the drive belt with the platter and this will decrease or stop with time. Also you might try removing the belts from the motors and watching them run freely to see if one is more jerky than the other. Mine is running smoothly with barely notable motor and contact noise.
I hope this helps. I don't consider myself an expert on this, or anything really, but this is what knowledge I've gained from my experience so far.