Have you tried changing your upper tension when you are in the quilting mode? My older Singer would do stitches like that when I sewed heavy fabrics unless I tightened up the tension. However, this article contradicts my experience, but does describe yours.
http://www.sewingreviews.org/correct...hooting-guide/
Last edited by Barb in Louisiana; 04-22-2018 at 06:35 PM.