VIVOTEK - Built with Reliability
 
User's Manual - 55  
5. Why live view is unavailable? 
The default live view receives a camera's stream #1. If a camera's stream #1 is congured using 
MPEG-4 
as the video codec, the following message will prompt.    
You can go to the Settings > Camera > Media > Video window to congure the video codec of 
stream #1 into H.264 or H.265.