YouTube supports 5.1 sound out of the box in selected devices, but not in web browsers, at least on the date I uploaded this video. So, you'll need to play the video using an external player. I use PotPlayer. Here's the tutorial:
[ Ссылка ]
Note that the codec YouTube uses in surround is AAC 5.1 384 kb/s, so the audio in these videos don't use the codec and may not have the speaker count advertised in them.
