rnr motion error

Hi guys,

New here (and in cnc production also) and i really need some help.
I bought a guess China made CNC 4 axes. Got some issues with the usb cable - problem solved.
I have encountered another problem today: the machine worked fine for couple of hours then my mach 3 program stoped working. Had to restart the computer. After restart, all settings from the software were gone.
I reseted all crap and the machine is working fine without the router turned on. The programs starts well, i can control the axes, but once i turn the router on nothing works. Cant control the axes, and the program is not working. When I shut down the router, everything is back up to normal. Also, from time to time, mach 3 shows the RNR motion error.
I have reinstalled Mach3, checked windows settings - all good.

Help.

Thx