Still no sound ...
Re: No sound
I have chromium-codecs-ffmpeg-extra, flashplugin-installer and pepperflash installed (kubuntu 16.04, latest beta version of Vivaldi. I do not have adobe-flashplugin installed. I think I got rid of it when it was giving my software update system (muon/apt) fits.
Everything at http://www.quirksmode.org/html5/tests/video.html plays fine in Firefox and all of it plays in vivaldi - but with no sound.
What do I need to fix?
I read a bit at gist.github.com/ruario/bec42d156d30affef655, but it was mainly confusing.
I thought that when I upgraded to 16.04, this stuff would work.
Are you sure your sound system not muted?
That ruario page introduce
latest-proprietary-media.shto download chromium-codecs-ffmpeg-extra. And how to build