Originally Posted by
PaperPrincess
It's shredding at the eye of the needle. Before taking it in for service, try a jeans or topstitch needle. They have a larger eye causing less stress on the thread.
I agree with PP. Also, are you using a vertical thread pin or a horizontal? I found that my Bernina likes the vertical pin better. Some threads twist as they come off the horizontal.
You didn't say what size thread and needle you are using. The sizes have to work together.