I have a Sweet 16 too. Do you have a thread net on your cone of thread. I find that helps. Also, if you're working on a big quilt like that, sometimes the bunched up quilt can get piled up and in the way of of the thread path and and cause that problem. If you've never changed your needle, you probably need to
And your domestic machine needles are different. Just for reference, look on the HQ website and you can see a picture of the type of needle you need. You can use a business card and slide it between the tension discs to clean out lint that may be stuck it there. Good luck! P.S. There is another good forum specifically for the Sweet Sixteen on Yahoo groups.