Originally Posted by Cybrarian

I'm no expert on machines, but I'm not sure the fleece is the problem. Unless you tried sewing on something else and the tension was fine? When I'm having a problem like you describe I go down the list, sewing a line of stitches on a scrap at least similar to my project to check if I have solved the problem. My list includes: rethreading top and bobbin threads, changing the needle, changing the bobbin, trying a different thread, cleaning out the bobbin area. Hope you find the problem, Humpty Dumpty's cold!