THIS IS HAPPENING TO ME, too, and I got the same response from Makerbot in that they want $100 just to talk to me, won't diagnose over email or phone and want me to ship the entire unit back to them for mystery diagnosis and repair. With a host of new, comparable printers on the market for at or near $500, what the hell are they thinking? It would be a hair more to buy a whole new printer than it would be to send mine back for repairs.

At any rate.. rant ended, problem below:

I had intermittent "skips" in the X axis during prints, which screwed up the whole print, of course. I troubleshot the issue to the best of my ability and determined that the shuttle moves freely and without binding, the belt is tight and is not slipping, and the stepper motor itself is not the issue (as I bought a replacement motor from Makerbot thinking that it had to be the issue.

No luck with any of those solutions.

I'm at a complete loss now, but seeing that someone else is having the same issue is giving me hope that this is a quasi-common occurrence and someone, somewhere may have come up with a fix.

HELP!