Sorry to hear of your troubles. I also have the Bernina 820 & for same period of time. Mine is 20 months old & at first it scared me to death but the dealer was fantastic & helped me thru the learning curve. The only problem I have had is usually with the bobbin & it's usually something that I didn't do right. The only other issue has been thread. It seems to be pretty particular with the type of thread I use. Maybe that's what your problem is. Have you tried other thread brands to see if that could be the source of your troubles? Might be worth trying. I feel for you as it is incredibly frustrating when these "beauties" act up, somewhat like a teenager !!! LOL Don't give up just yet as you can always trade in (or whatever) when your timeline suits you. Best of luck.