I am a fairly new tech but have had other tech who have been around awhile work on this same issue. I am getting small black spots on prints, copies. The longer it goes on the worse they seem to get. We have replaced the process unit 3 times. Goes away for a few weeks maybe a month then returns. Replaced toner with one of the process units. I then replaced the transfer roller and they then went away for a few weeks but are now back. Anyone seen this or have any ideas.

Same old question.... Are you using OEM toner?

I'm betting not OEM toner, used to happen when we tried Katun toner.That certaintly never saved us anything in the long run.

Yes it has OEM toner. We supply it with their maintenance contract. And I installed it myself.