I don't know anything about that machine but it sounds like maybe the tension discs are not opening/your thread is not in the right groove, look at your disc as you raise and lower the foot and see if things are opening and closing right. I've heard of pulling about 12-18 inches of unwaxed dental floss through them to clean, can't hurt. good luck, I know the feeling of wanting to pitch it out, I would have mine if it weren't so heavy!