I have a Janome that did that.I took it to the LQS they said I needed a new foot pedal for the machine. I think It was $100. About a month later it started doing it again. I went to a different LQS and they fixed it. Not sure what they did. There was a thread on here a while back back about Janomes doing this. Some said to take the foot pedal apart and clean the inside. Some also said it was nearly impossible to get it back together. I never tried that.