Please try to upgrade your DVR to resolve this issue.
The below is the detailed steps to upgrade the DVR:
(1)please go to download center to find the correct upgrade file according to the model name.
NOTE: The model name is stated on the mini label on the bottom of the DVR.
(2). You needn't open the upgrade file, please directly download and unzip the upgrade file
to your U-disk.
NOTE: Please save the upgrade file in the root directory.
(3). The file's name should be the original one, can not be have any changes,if the file's name change to others, the upgrade will be failed.
(4). Before starting to upgrade, please remove the mouse and unplug the power supply, then plug the U-disk into the DVR's USB port, and plug the power supply.
(5). It can upgrade automatically as long as it has electricity, the upgrade process need to last several minutes, please be patient.
(6).After upgrading, please go to DVR's main menu – information System to check if the firmware version is V 1.1.5 or not , if
yes, that means upgrade successfully, if not, please try to change another USB to try again.
NOTE: The system doesn't support SONY brand USB.
(7).After upgrading the DVR firmware, if the pictures on your monitor is black and white, please change the video format to PAL via DVR Main Menu-Setup-Basic.