Thanks!
Correct - it's all down to whether the browser can play the codec. If it can't, then there is nothing that my plugin can do about that - the plugin is intended to display the ability to play the audio/video items, from there it is up to the browser, and its user(s), as to whether it can play (as indicated in the plugin description, there is a link there that can help people determine if their browser can play a certain format/codec combination)
Sorry, but there is nothing (to my knowledge) that I can do that will force a browser to play a video in the native HTML5 player if it can't support the codec that is used.
What I can do is try to check the codec that the video is using and then not display the player if the browser doesn't support it, with a clear indication of why the player isn't displayed to that user. I've still got a little work to do on a planned update for a previous issue, and will start looking into adding that functionality (if that is achievable then I might be able to incorporate a fallback to a player such as videojs....no promises though. Maybe even provide an option for the admin to determine whether to use the native player or to use the videojs player.....hmmmmm)