Nocking noise is usually bad IBT assembly (CRU). Reinsert color toner usually means replacing the drum(imaging kit) for that color (CRU). But as you are getting nocking noise I would try belt first
Your printers are under waranty, so you will need to call the printer provider to replace the black toner or even the printer.
We have received 10 New Xerox VersaLink C400 printers here at the Police Department. The very first one I set up is having problems with the black toner. The error states "reinsert Black Toner and restart Device (092-321). I check the toner there is still some toner in the cartridge, but when I remove and reinsert, it still gives me this error and will not print.
Plus it makes a knocking noise when starting.
Milwaukee Police Department