Yes, the film plays back at the full bit rate of whatever it would've been on the original disk.
My Shield is connected to my router directly and so is the PC that the server runs on. Both on gigabit LAN.
In the Plex app settings on the Shield, playback for audio and video is set to original. This stops the PC doing any transcoding, which could be a potential bottleneck to playback.
The other potential bottleneck is writing to the drive with the Blu-ray rip on at the same time you are reading from it.
In my experience these are the only two things that cause buffering during playback on an Nvidia Shield.
Are you using a USB hard drive to store the film's? That may also limit the read speed, because of write cache. This allows the drive to be disconnected without loosing data. I found that disabling this increased the transfer speeds from around 40mbs to over 100.
Hi,
I had it connected PC - Gigabit switch, Gigabit switch - Xbox One S.
Both in the same room, just as a test. I have an ethernet cable from downstairs router to upstairs bedroom into gigabit switch. From switch it goes to TV,PC,Xbox One S
Films are on an internal 3TB HDD. Nothing else was happening on the PC at the point of streaming to Xbox via Plex.
As you mentioned I had all the settings at original to keep it all native.
Maybe I should try again, this was in the very early days of UHD discs being dumped. I got an Xbox One S for the sole reason of UHD playback in fact haha.
Cheers,
Sean