not sure if you can hook vlc into the stream from TBS tuners, but, I use it to playback mpeg-2 interlaced media on windows without hardware acceleration,
and (apparently) uses same algorithm as the shield, which you might want watching sport.
I don't see why plex dvr doesn't have the same mechanism as vlc, or the expensive dvr 'channels' app,
alternatively if player is on a smart tv, they can natively decode the freeview streams, so can't plex avoid a transcode there ?
Do you nonetheless store recorded live tv streams as h264 ? (offline it overnight ... think we may have discussed that with andy in earlier thread)
Also, saw below, I'm hoping roku does not impose an update, since I have had problems with radio plugins compatability, on the windows system I use for plex server.
Plex debuts redesigned TV app on Roku & Apple TV (beta)
[http://www.digitalfaq.com/forum/video-restore/7688-best-convert-mpeg2.html
https://www.reddit.com/r/PleX/comments/7smb36/why_does_plex_always_transcode_live_tv/
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