Also, check your wheels..they may have gunk on them or the rubber "tires" have worn and need replacing. I find it helps to have someone else move the machine while I look at every nook and cranny to find my problem. The machine should be turned off..just have them move it over and over the area until you see what's catching. With mine, it was the board that the panto sits on, a screw has loosened and it was higher in that area, but it could be anything.