Has this been an ongoing problem? Did it just start? Have you had it sitting for a while. Maybe just needs oiling and run a bit to get back to "normal" use. I'm guessing that it is not the stitch length regulator just moving. I've read of that happening.
http://www.oldsewingear.com/1/post/2...-selector.html
Janey - Neat people never make the exciting discoveries I do.
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