Board hangs

I have this one board. When I start printing pronterface every time cause by this errors:

Print ended at: 13:58:37
and took: 00:01:12
Print Started at: 14:03:08
Error:No Line Number with checksum, Last Line: 66
Error:No Line Number with checksum, Last Line: 66
Error:No Line Number with checksum, Last Line: 66
Error:No Line Number with checksum, Last Line: 66
Error:No Line Number with checksum, Last Line: 66
Error:No Line Number with checksum, Last Line: 66
Error:No Line Number with checksum, Last Line: 66

After I can try again only after psu switching. I exclude PSU noise because I try to use Bench Top DC PSU HY3005C. I also try to use another power supply for AVR and ft232 cuted off and use usb +5v power.
There is one interesting thing which I found. If unplug all motors or only Z motor attached - errors don't appear and pronterface printing normal.

If you are using a +5V regulator, is it getting hot when you start the print? I noticed cheap StepSticks [reprap.org] can draw 17mA each when asked to turn on.

Can you manually control the printer without these problems? (E.g. sending G-Code manually with a terminal, or in GUI to tell it to move the motors around, extrude, heat up, etc.)