Melzi stops at last 3-5mm after firmware update [solved] (1 reply)

Hi all.
I have reprap chinese printer with board marked as "Melzi Ardentissimo" with ATMEGA1284P/AU1328.
After extruder upgrade i decided to update firmware.
as i got from reprap wiki - with this board i can use firmware for Melzi.2.0
i've downloaded Sprinter, changed config to

// Sanguinololu 1.2 and above = 62
#define MOTHERBOARD 62

,
changed callibration and did upload.
it looks good, but i got some strange bug: all my prints are stops 1-5mm (z) before end of model.

i tryed:
print with sd card
print with usb (pronterface)
print from sd, but with pronterface commands
slice with cura
slice with slic3r
reupload firmware

nothing helps =(

printing fails at same point within one model. another model will fail at other point, i can't see any relations.

what to do? =)