I agree with Dolphyngyrl. sounds like there's something in the tension disks. The way I've cleaned them is to crank the tension as LOW as it will go to loosen up the disks, then take a piece of unwaxed dental floss and floss between the disks. See if you get any fluff that comes out. Use a longish piece and don't go back and forth as that might just drive whatever's in there farther in. Go in one direction and draw the floss thru. You can also use a piece of heavy thread, like buttonhole twist.