"Unknown command / wrong checksum" What kind of Problem it might be?

I have just assembled a Rostock mini and the Repetier-Host got following error while I try to connect the printer.

17:02:31.589 : ok 3
17:02:31.589 : Unknown command: Y0.00 Z0.*?.0000
17:02:31.790 : Resend:4
17:02:31.792 : ok
17:02:32.620 : N1 M110 *2
17:02:32.625 : ok
17:02:32.626 : N1 M110 *2
17:02:32.629 : ok
17:02:32.630 : N2 M115 *4
17:02:32.633 : ok 2
17:02:32.637 : N3 T0 *25
17:02:32.668 : FIRMWARE_NAME:Repetier_0.83 FIRMWARE_URL:[github.com] PROTOCOL_VERSION:1.0 MACHINE_TYPE:Rostock EXTRUDER_COUNT:1 REPETIER_PROTOCOL:2
17:02:32.668 : ok 3
17:02:32.668 : N4 M105 *3
17:02:32.674 : Error:Binary cmd wrong checksum.

Firmware ? Driver ? or any other problems ?