don't be afraid to adjust your tension both on top and bobbin. I use a Towa gauge for each bobbin--even if the same thread, sometimes I find that I wind the bobbin just a little different--especially when I'm switching between colors. I prefer to adjust the bobbin and leave the 2 tops tensioners on my Gammill alone. But some threads to require I make a top adjustment too. I recently used Magnifico (Superior, like Glide) for first time and really had to loosen the intermediate tensioner. Check the Bernina website for video tutes and also sign up for the Bernina FB page for more help from folks that own the same machine.