Just replaced the imaging unit on our Phaser 6300, as I thought that was the culprit.
Getting magenta cast on entire page, even though the rest of the output is fine. Ran 20 pages, and magenta covered all 20.
Inside, there is magenta toner on the imaging unit roller.
What could be causing this? Just sunk a couple hundred into an old printer....
If toner is getting dumped on the roller then the toner cart is the problem