Preview Black Screen on Multi Split Screen

Problem: Single screen preview is normal, but when switching to multi segmented screen preview, the screen is black

Solution:

1. If it is a fixed channel with a black screen, confirm whether the camera's sub stream is enabled, and it is necessary to enable the sub stream.

2. If it is a random channel black screen, it may be a decoding problem with the video recorder. The resolution and stream value of the camera can be reduced, and the version information of the video recorder can be confirmed and the program version of the video recorder can be updated.