I have had lots of trouble with my machine. Like others, I will be half way through a quilt and all at once I get the "bird's nests" on the back side. I have switched needles, switched thread, loosened and tightened my material and both tensions. Once it happened after I refilled the bobbin. I fill my bobbins with a Side Winder and am wondering if it winds the thread too loosely. I'm so exasperated! I would just love to turn out a nice looking quilt on my Voyager 17. GrandmaAlice