Hi there,
I have exactly the same problem as you. and I'm still stuck with it, I've tried everything that may come to mind, nothing useless.. Simple small designs (cubes) print with no problem. bigger more complex designs will stop at a random point, and most of the times the print will shift in a random z level. if I try with USB, I get the "Packet timed out" error.. !!
Have you solved your problem or still suffering as I am ??
Thank you in advance