Originally Posted by MadQuilter
Just for grins: What happens to stitch length when you change it on regular pieces of fabric? Does it change?
What batting are you using? Does the sandwich travel easy through the machine, or do you have to pull and tug?
I agree with these questions. Make sure that the machine stitches normally on two pieces of fabric first. If that's okay, then I wonder if the batting is too thick for the machine to handle.