You should be able to find a clue if you check the system logs for alarm events for that channel.I can't find any enabled alarm that would cause this
What's the model of NVR and the firmware version?
You should be able to find a clue if you check the system logs for alarm events for that channel.
Configuration | Maintenance | Log
Agreed, there should be lots of gaps based on what's shown in that log extract.I would have expected it to only record between those stop and start events.