Does it sew normal when you are doing piecing? If so, you may need a larger needle when quilting. For instance, I piece with a 12 or 14, but if I am going to do quilting, I may try a 16 or 18, the latter of which is used for leather. I have a high end Brother, or at least it was 10 years ago, and it won't sew heavier material with a finer needle.