A firmware update was recently released for the NVR6XX-4KS2 series devices.
Information, instructions, and download links can be found Here
From Dahua Wiki
The device failed to record video and snapshot
- Device failed to take snap shot for motion event. From the local recorder menu , check the if the if motion detect for that camera is enabled, check if snapshot is checked off under the event settings. Make sure you apply and save.
- Device failed to record a motion event. From the local recorder menu , check the if the if motion detect for that camera is enabled, check if record is checked off under the event settings. Make sure you apply and save.
- Under schedule you will need to make sure it the schedule is set. Motion detection (MD) under the schedule needs to be also check off. Setting the schedule ensure the system will detect events such as Motion Detect in the date and time you set it for. Failing to do this will result in no snap shot.
- Time period might not be set. Set “video time period”, “snapshot time period” in the WEB interface; please refer to the manual for more details.
- Check if the “memory point” enable in the WEB interface is checked.
- Check if the connection of SD and FTP of video and snapshot storage is normal, try to connect FTP to the computer.
- Set “video mode” as manual or auto in the WEB interface.
- From the WEB interface , make sure snapshot is set to "trigger". Under setup > image > encode > snapshot > mode > select trigger. This should work for IVS (if available), face detect and
Possible reason: “Snapshot time period” is set wrongly; storage path is not correct; “video mode” is set as off.motion detection if the snapshot box is checked off or selected from those event features.