Oh my goodness. It took my two years to figure out what was wrong with my new Bernina. It acted horrible. I finally bought a CONE of Gutermann thread and it purred. Now, I don't know if it's the cone or if it's the cone of Gutermann, but I bought a cone of another high quality brand but am kind of chicken to try it yet. My machine is doing so well, I don't want to have any more problems again. And to think for two years it was the thread. So, yes, thread can make all the difference in the world.