e-Studio 456 and 457, offsetting from the fuser??

[Oystercopy]

I've had several of these machines do this; they will randomly start to leave toner on the BACKS of the pages and do it for like 50 pages, then start fusing as normal again and everything goes away... I had it happen once in my shop on my bookkeeper's e-456 and now I've got a customer's e-457 doing it as well. In fact, now that I think of it, I had it happen for a very short time in an e-457 that I sold the week before as well.. was right here in my shop and my first thought was, "Oh, I didn't rebuild the fuser on the machine yet!" but I HAD... weird.

All the FW is up to date on all these machines as well, FYI.

Any advice much appreciated!
OC

[blackcat4866]

Take a look at the lamps. I had an eS455 that kept blistering the same area of the heat roller. The center heat lamp had an obvious discoloration which I believe to be a hot spot. I'd heard of halogen lamps with hot spots, but never actually seen one before that day. I've not had to work on that fuser again. =^..^=