A firmware update was recently released for the NVR6XX-4KS2 series devices.

Information, instructions, and download links can be found Here

Troubleshoot/NVR/Video Loss 1 Camera

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Video Loss 1 Camera

There are following possibilities:

  • Firmware is not compatible. You will need to upgrade to the latest version.
  • Brightness is 0. Please restore factory default setup.
  • There is no video input signal or it is too weak.
  • You will need to check the network cable.
  • DVR hardware malfunctions.