Troubleshooting: Bobbin tension issue resulting in tangling thread. Here's the fix: EDIT: This problem has been resolved. There was nothing wrong with the machine, it was the quality of the thread that's been going through it. A simple cone of poly Coats & Clark had shed so much lint inside that I had to blow it out after removing the plate and the bobbin case. I will not be using Coats & Clark again. I switched to Aurifil thread after cleaning and the problem is gone.