Hi - I have had my Husqvarna Sapphire 960Q for about a month and I am not able to get the free motion to work properly. The thread shreds and then snaps and the stitches are not good. Any tips or help? I've tried stitching with 0 stitch length, 2.5 stitch length etc. I have tried using Coats and Gutermann thread which both worked on my old Toyota but shreads, bunches and then snaps. What am I doing wrong?