we have seen many self reset issues that are related to power, one of the most common is failure to secure the ethernet cable to the radio so that wind and other things can not easily disconnect the cable or shake it hard enough to cause intermittent power resets (too many can cause radio to reset to factory),
Other common issues are mains power fluctuations, bad/poor cable crimp/tool worn out, CCA cable!
There is always a chance that it is faulty hardware but that is not as common in the last two revisions as it was.