I have a 3245c with light copies, the prints look good. I cleaned the optics and performed auto color calibration,which brings the copies back to about 90%. After about a week the copies are light again.
For some reason on these machines you have to get the mirrors very clean.
I usually just clean dusty optics with a dry lint free cloth, but have found on these machine that you have to cleaned them with a cloth and some cleaner.
Just a thought!!