I also have that machine. Same problem. I have sent to the repair man time and time again sometimes not even taking from the shop before I tried it again. Still doing it. I am sure there is some sort of burr underneath . Sews fine with straight stitching but when I try to do free motion slowly (as around a motif) it shreds. So I have sent it back yet again. Have also tried new needles (as recommended by the machine shop) new cottons. will be interesting to see what repair man has to say this time.