A couple of additional tips for you. The auto threaders don't usually work with the INV thread. You have to thread the needle.
Slow the machine speed down and don't sew at the fast speed.
I use a thread stand and place it behind machine. It allows the thread to come off the spool without twisting. If there are kinks the thread will break. I don't adjust tension on my machines so have no advice.
Good luck!