Try cleaning your machine of all lint after you make each quilt - especially with the plate off and bobbin case out. Brush the inside of the bobbin case as well. That is just normal part of maintenance for your machine. I suggest using fray stopper on the hole. If you are really concerned, you could fuse a small heart or square patch over it.Change your needle regularly as well - especially if you hear the popping sound as it goes into your work. That sound means that the needle is very blunt and needs to be discarded. All the best with it.