Xbox One S - Playback shutters/buffers a lot

[dank373]

Server Version#: 1.29.2.6364
Player Version#: 2.108.1.70

Hello, I try to playback on my Xbox from my Plex server (locally) that runs on my custom-built NAS (TrueNAS Intel(R) Core™ i7-10700T CPU @ 2.00GHz / 64GB RAM) some demo videos that always shutter or more often starts to buffer frequently. The demo videos are from here: Dolby Trailers - The Digital Theater the Dolby ones. Xbox is wired with 1Gb no wifi configured, the NAS is wired with 10Gb, no wifi card. Direct play enabled, with and without direct stream happens on the Xbox. On PC it goes flawlessly. On my LG TV (WebOS) I can’t play it as the directory does not show up…
Copying the video to a USB drive and playing it directly on Xbox with the VLC UWP app, goes also flawlessly.
The strange thing that I noticed while I looked for the network is that it transfers only 10Mb a video which has a 25,2Mb rate and can peak to double that.

Some examples:
|Nature’s Fury (Lossless - ATMOS)| MKV H.264 1080p| Dolby TrueHD 7.1 ATMOS
|Leaf (Lossless-ATMOS)| MKV H.264 1080p| Dolby TrueHD 7.1 ATMOS
|Chameleon|M2TS H265 2160p Dolby Vision
M2TS H265 1080p Dolby Vision|Dolby TrueHD 7.1 ATMOS
Dolby Digital Plus ATMOS|

Other lower-rate videos seems to work fine, like 720p stereo.

[dank373]

Hah, I found the issue. The B pair in the cable had some issue and therefore the negotiation ended on 10Mb, which I found while I analysed my network traffic and I noticed that it never exceeds 10Mb for that device… And then I looked at what the switch wrote where it confirmed the 10Mb, and the switch cable test told me that the B pair is broken. So I terminated the cable and now works fine.

However, it’s still interesting that Plex did not detect the degraded connection and did not start to stream a lower-quality video…