I know this is an old dog, unfortunately I still have a few in the field. This one has the white voids going front to rear. I've replaced all of the clutches, Transfer section has been rebuild, tried a different imaging unit, Main and T/S have been changed and nothing works for longer than a day or two. I'm am wondering if I'm losing DV Bias or the HVT is going bad? It's just about the only thing I haven't replaced. I know this problem is usually caused by one or more clutches or the Transfer belts stalling but this one has me stumped. Anyone have any suggestions other than replacing the machine, which customer is not going to do right now. Thanks.

how about drum ground.

This turned out to be a bad Registration Clutch out of the box. Chinese crap!