Well I have Bernina 830 top of the line one and its seems to lock up now and then and only the repair guy can unlock it so this happened, took it in and the owner b\put on the bill may cost $100 and I asked about that and she said she said he can't be working for nothing anymore! So guess he cleaned out the lint in the top and did some updates and cost me $75!! He never charged me before and still uner warentee until next Apr!