I found also that the actifeed is very sensitive to bobbin problems...not only cleaning under that spring, but look inside-there is a notch inside where the thread goes that also fills up with gunk. Keeping it clean makes a big difference. And on the thread sensor 'bar' behind the threads, gently rotate it...pointed out a month ago by someone, and I had a tech tell me to do the same...don't know what it does but it made a difference. The actifeed IS strange...will take some getting used to. I have it running fine for a batch-then suddenly it acts up...then next time (different fabric or hat) and it runs fine again. But it is more and more 'good' and less 'bad' as it goes. Roland