I wrote Baby Lock yesterday about the problems I am having with the Jazz 2. I am guessing it will be next week or so before I get a reply.
I tried setting things up again with the Jazz 2, and for a while the machine cooperated, doing very nice stitching, then it started doing the same huge lashing on the bottom. I didn't change anything in the way I was moving, or the speed I used. It just decided to be ornery. I do think there is something wrong with the tension system.
I noted that the Jazz had a different setup than the Jazz 2 when it comes to threading. Not sure why it was changed in the upgrade process. Maybe it was cheaper, or maybe it actually improved things.
I'm not sure just what the machine does when you raise or lower the tension. But whatever mechanism is in play, it is not working as it should. I hate to have to take the machine to a repair shop. It's brand new. I just hope BL customer service can tell me just how to cure the problem.