There are two kinds of video delay measured by UI3. You can see both of these graphed in the "Stats for nerds" panel (right click the video player).
1. Network Delay (The estimated video delay caused by insufficient network speed. Values of a few hundred milliseconds are completely normal and nothing to worry about.)
Network Delay is computed as the difference between the expected video timestamp and the actual timestamp of the most recent video frame you received over the network. E.g.
Network_Delay = Expected_Timestamp - Last_Received_Timestamp.
When Network Delay rises above 2.5 seconds, you get this message:
Your network connection is not fast enough to handle this stream in realtime. Consider changing the streaming quality.
2. Player Delay (The estimated video delay caused by insufficient CPU speed. Values of a few hundred milliseconds are completely normal and nothing to worry about. A small amount of player delay is often intentional in order to keep the Frame Timing Error as close to zero as possible.)
Player Delay is computed as the difference between the timestamp of the last video frame you received over the network and the last video frame that was displayed on-screen. E.g.
Player_Delay = Last_Received_Timestamp - Last_Displayed_Timestamp.
When Player Delay rises above 6.5 seconds, you get this message:
This stream is becoming very delayed, which may indicate a compatibility issue with the browser you are using. Please try a different browser, or open UI Settings and change the H.264 player to a different option.
If your network is performing inconsistently, you may see both warning messages, one at a time or both together, as a result of video pausing and arriving in bursts that are large enough it takes the video player a while to work through each burst and get back to low delay. UI3's HTML5 player in particular works through buffered video relatively slowly. You may get better results from switching UI3's H.264 player to the "WebCodecs" option, which should be selectable in the UI Settings since you have HTTPS available.
