Have the same problem with my Babylock thought it was me but on my 15-91 I can sew a stright line can even let go and the material feeds in stright so I use her to do my stright stitching. Think it has something to do with the feed dogs being closer together than on the newer machines for zig zag material is being cought by both not just half. Any way that thought works for me and that is my story and I am sticking to it. lol