I've had this for 2-3 years or so now and been happy with it. However recently I've heard a constant "click, click, click" after each print job. The clicking is fairly loud and continues for a bit, then slows down, quiets down, and stops. Sounds like it is coming from the top, rightish side. I'm concerned this is going to become a bigger problem and would like to nip it in the bud before it does. Looks fairly easy to get into the guts of the printer. Please advise. I've been a proponent of Xerox printers so far after my pleasant experience with this one, so far.