There are lots of people unhappy with their 830's. A yahoo group has been set up for those with defective 830's. Mine was in the shop more in the first 2 years than in my sewing room. It's been behaving well after having 5 sensors replaced, two springs, embroidery mother board and multiple other parts and repairs. It's always fun when people chime in that most problems are due to user error. LOL. It's not user error when the hardware on the machine dies or parts literally fall out in your lap!
You should look into the defective yahoo group.