Hate bringing up old threads like this but I want people to be set straight, youtube DOES in fact support 5.1 and 7.1 audio tracks. This is stated in youtube's audio upload format compatibilities and I have tested and verified that 5.1/7.1 dd/dts/atmos audio tests that were properly uploaded DO in fact work with my 6 channel analog audio outputs and dolby-digital-live enabled toslink audio output in Edge, Internet Explorer, and Firefox but will not work in Chrome nor Opera.