Hi,
Really sorry to hear someone else is having problems. Originally I couldn't get either the ruler mode or cruise mode to work and discovered the back encoder wasn't even touching the rail. After I adjusted the tracks and made sure the encoder was riding on the track it magically started working. The speed control should adjust the speed/stitch length while you are stitching in speed mode?? I would try backing that off and see if it slows down for you. Went to the show today in Sarasota and learned so much I am sooo glad I went. Good luck Judy