I sure hated when my 7700 did that, so very hard to keep that end of seam straight. I think it has to do with the design of the feed dogs & that O2 1/4" foot. Together they seem to push the fabric to the left. I did purchase a new 1/4" foot for my Baby Lock & tried it on the 7700, it worked much nicer & the seams stayed straighter. I only paid around $6.00 for it off Ebay. The only difference I could tell was that the 1/4" guide on the right of the foot was not as deep as the O2 foot. If you can find a foot like that it may help tremendously. Did sell my 7700 after buying my Baby Lock, got pissed at it because that exact thing happened way too much.