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 All Cameras

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Video Loss on Multiple Cameras

There are following possibilities:

  • Firmware may be old. Please upgrade to the latest version.
  • Brightness is 0. Please restore factory default setup.
  • If There is no video input signal or it is too weak, due to the length of cable, find shorter cable.
  • Check privacy mask setup or your screen saver and remove them if possible.
  • If DVR hardware malfunctions then change hardware.
  • If Not enough bandwidth then check internet.
  • If Insufficient power then check and change power supply.
  • Check if you are using You are using aluminum braid or copper braid cable and change if not.