One of my machines will stop and beep when the bobbin gets low. What's annoying about this is I usually have 2 or 3 inches left to sew, and I know there is 9 or 10 inches of thread left on the bobbin. So I hit the "Ok" button, hit the gas, get maybe 2 stitches along, then it stops and beeps again, and won't start unless I either hit "Ok" or replace the bobbin. It gets infuriating.