I have a Bernina 820. I made a baby quilt and started to quilt it. I used Mettler thread in the bobbin and on top. I kept getting lots of skipped stitches, some of them quite big. It looks as though the needle did not go through the fabric at points. I took out the bobbin and top thread and made sure there was no fuzz or anything else and then I rethreaded. No luck. Can any of you out there give me some suggestions? Thank you very much for your suggestions.