That your content and games are stereo. 5.1 is rare on flash, YouTube videos.
My 5.1 audio set-up doesn't really work like it should. In BSplayer, VLC etc. it doesn't work even with filters like mixer, not in HTML5 in Chrome or Firefox, not in Soundcloud.
It does work in Flash-videos, foobar2000 because of a channel mixer plugin and some games. I wish it worked in everything, even if just upmixing stereo to surround. I have Windows 10 but the same problem was there in 8. I have RealTek audio drivers and there isn't a speaker fill option. How can I make the most out of my 5.1 audio-setup?

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