My problem was with the empty bobbin sensor. It would pop up a hundred times doing an embroidery (I have an 830) and less on regular sewing. It happened since I had it. I was able to push the button and continue but it was a real pain and took the fun out of using it. I was ready to send it back to Bernina in Chicago area and gave my dealer one last try. I took my hoops, quilting samples, sewing samples, etc with me and sat with him showing how it kept popping up. They (salesman and technician) tried everything, even calling Bernina. There are apparently 8 sensors on the Bernina. They ended up replacing a sensor and it works great now. My problem was extreme but if it continues, I would insist on going to dealers when technician is there and staying until it is fixed.