When the Monitor Software performs round robin for a long time, the live video is lost during the preview. Some video windows have black screens.
1. Stop round robin.
2. Switch to the distribution where the video is lost. Close the window of the lost video and then open it again. The video is played.
3. Restart round robin.
Each round robin distribution has the video and this video is not closed during round robin. When the video are lost, the local record of this video can still be played by the special player. This fact indicates that the data forwarded by the NVR and the data received by the client are correct. Why the video cannot be played in Monitor Software is that the decoding library breaks down and cannot work normally.