A friend gave me a tip that I hadn't thought of before. Using canned air (like for a computer or keyboard) to clean out the bobbin area. I am fairly particular about the bobbin and keep it brushed out, but was having trouble with lint build-up. A puff or two of that canned air just made so much difference and far better than a brush has ever done. Now I keep it by my machine and hit it with a puff or two about every time I change the bobbin. Isn't it aggravating when the thread does that? Makes me stutter and stammer.....