Report "My White Speedylock 1600 serger is making a clunking sound. The part where the right and left needle threads go behind the front tension plate (right before you pass it through the needles) keeps hitting the cutter. Something is obviously out of alignment but I can't figure out how to fix it. I've replaced the cutter and the needles but still have the "touching" problem and the "clunking" sound. Help!"