Plex Media Player 3 (Windows 7) does not play/decode EAC3 5.1 or TrueHD 7.1

Plex Players Desktop Players
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4

Here it says Win7 or later:
https://forums.plex.tv/t/plex-media-player-3-0-windows-and-mac-forum-preview/

And Plex “works” - just not with the aforementioned audio codecs. But if this is indeed a Win7 issue, then that would be great to know.