Last night I took a mini-course on machine maintenance that can be done at home, in between professional cleanings. The biggest culprit seems to be lint build-up! The one place we, as the machine owner, doesn't clean are the tension disks because (1) we're scared of hurting them and, (2) we can't get at them. I learned last night to take 3-4 strands of thread (what you usually use) about a foot long, tie them together in the center with a knot, and run this back & forth through the slot where the tension disks are. This will remove the lint that is built up on the axle/connection point wehre the two tension disks meet. It's worth a try. Good luck!