Hello Ethor,
I apologize for the late response but to be honest I have never really figured out what makes these units periodically reboot. But I have narrowed it down to the point that it seems this only happens at certain locations, meaning I have switched out problem dvrs with new ones and the same problem occurs. When I bring the problem units to test at home or move to another location, the problem goes away. I assume the problem is related to the power service in the building. If you have to reset monitor settings every time a reboot occurs then I would suggest changing your setup.