I have a Memory Craft 350E and only in occasional places the hoop jumps across one stitch. I can't find anything the matter, I have taken the hoop off and checked all around the machine, I've taken the bobbin out and cleaned it out. I have changed the needle and now it seems to be getting worse. It's like it gets stuck then lets go to give a jump. The fabric & other items on the bottom & top are all tight. I can't think of anything else it could be. Do you have any suggestions please. Thanks. Diane