ZMD-DX-SIL8 with V70.3.018 latest update.
It started a few days ago in the evening it would reboot on the hour from 7 to 11pm. Last night it started rebooting every 5 minutes and sends out a bunch of “lost video” alerts each time.
Try unplugging the cameras from power, and then rebooting the system manually. Once up, reformat the hard drive (with the cameras still powered off) .
If the issue happens again in the next 6 months or so, it would point to a hardware issue.
Exactly as Patty said. My experience with reboots is failing to reformat the hard-drive from time to time. It can finally get so bad that the hard-drive can fail. One time, the DVR had to be replaced. Reformatting is a required scheduled maintenance for efficient operation.