Due to recent changes on browsers and the addition of Google Chrome's Media Engagement Index (MEI), autoplaying of videos with sound is heavily penalized and in most cases, is not allowed.
If your MEI is not high enough, any type of video autoplay with sound will be blocked by the browser if you do not have a valid user interaction with the player.
More information on this change can be found here - https://developers.google.com/web/updates/2017/09/autoplay-policy-changes
The player has an intelligent system in place which takes into consideration if you have any user interaction and how high your MEI is and depending on this behaves in the following way:
- If your MEI is high enough, autoplay with sound should work as intended. This also takes into consideration if you autoplay your video in a muted state and you have an option like sound on mouse rollover enabled.
- If your MEI is not high enough but the player has registered a valid user interaction upon the player, autoplay with sound should work as intended. This also takes into consideration if you autoplay your video in a muted state and you have an option like sound on mouse rollover enabled.
- If your MEI is not high enough and the player has not registered a valid user interaction which would allow autoplay with sound, the player will continue playing back your video without any sound and only once the player registers a valid user interaction will it allow sound in the player. For example, if your ad starts in autoplay mode muted and you have set an option for sound on mouse rollover, when you mouse over the player no sound will be heard in the player and your ad will continue playback without it pausing.
We think the above behavior of the player provides the best combination for autoplaying videos with and without sound.
You can check your Chrome's MEI for each specific domain by entering this in your browsers address bar - chrome://media-engagement