The tension settings for FMQ are different for everyone and it depends on the machine & the type of thread. I would open the tension all the way up and blow out any lint of anything that may have gotten caught in the tension disks. My machine actually sucked up a lint ball one time that got stuck i the tension assembly and I couldn't reach it without fear of scratching something in my computerized, auto-tensioning machine. My machine will also act up if even the tiniest piece of thread or lint gets in the way of the hook assembly in the bobbin area so I would clean that area out, too and wind another bobbin. Rethread the top with different thread (thread could be dried out & brittle) and floss out the thread path with dental floss if I still have an issue. Put some silicone or Sewer's Aid on the top thread to help it flow. Turning the spool upside down sometimes helps me and having someone else sew while I watch the thread path helps find problem areas.