This justed happened to me and I called the service people they told me to take it in, I'm still with out my machine, after cleaning and changing needle I had to tighten my tension. Everytime I wound a new bobbin(very clean, that wasnt the issue) I had to take my bobbin cassing out and tighen the screw each time, this machine isnt even a year old (babylock esante). So when I find out what the problem was I will tell you. I hope it's just that I might need a new casing