Problem with some 4K x265 mkv files buffering and then stopping

[dextose]

Server Version#: 1.17.0.1709
Player Version#: 4.5.1

As the topic states I have a problem with Plex where some files can play just fine, and others will start to play but after some time buffer and then stop. For some files its after a few minutes, other files its after 10-15 minutes etc.

At first I thought it was because the DTS-audio had to be transcoded. But some of the working files have DTS-audio too that has to be Plex Media Server.log (469.7 KB) transcoded.

Log file is added.

Any idea what is wrong? Is it the TV, or is it something with the audio?

[nibbles]

The devil is probably in the details of each film. Have you had any luck?

I noticed just the other day how the website article on buffering to a TV or similar player could have issues where high bitrates could run the device low on memory => stutter.

The HEVC specs that are used to encode 4K HDR include a few very high bitrate level@tiers, specifically 5.1@high and 5.2@main and 5.2@high.

The two easiest things to do are first Analyze your film in Plex, then investigate the XML Info for the media file possibly with various apps until you see all the info.

Some players just won’t like a main10@L5.2@high with bt2020 HDR color.
The audio is less of an issue, as it’s only a couple of Mbps trying to live next to a 100 Mbps video.

People praise the ATV4K because it handles these. I might get a NUC with linux and HDMI-2.0a. I doubt it’s worth waiting for something that supports HDMI-2.1. We just want seamless 4K, not 8K 4:4:4 chroma 12bit lols.

[dextose]

Nope it’s still not working as it should.

I just looked up some specs for the TV, and it should be able to play files with HEVC (H.265 Main 10) and a bit rate of up to 80 mbps.

When I analyze one of the films in Plex it will show me this: Bitrate 45117 kbps , Color Primaries bt2020, Niveau 5.1, Profile main 10.

If I check the same film in MediaInfo it will show me this: Overall bit rate : 45.1 Mb/s, Format profile : Main 10@L5.1@High and Color primaries : BT.2020.

Analyzing a working film with Plex will show this info: Bitrate 15297 kbps, Color Primaries bt2020, Niveau 5.1, Profile main 10.

In MediaInfo the same film will show this: Overall bit rate : 15.2 Mb/s, Format profile : Main 10@L5.1@High and Color primaries : BT.2020.

Is that helpful, and what can I do to fix it?

[nibbles]

@dextose

Is that helpful, and what can I do to fix it?

Definitely helpful. The higher bitrate film seems to be giving you problems.
Are you sending the data to the TV over WiFi?

The topic below is really good for wrapping your mind around the reqs.

[INFO] Plex, 4k, transcoding, and you - aka the rules of 4k

NOTE: for 2022 – Plex has come a long way since this FAQ was originally written, HW transcoding has become more available and more stable, and tone mapping was recently added to address the hdr/sdr color conversion issues. The first 4 ‘rules’ generally are no longer as important as they once were, but may still be a good thing to bear in mind. Dolby Vision, is an entirely other mess. THIS thread/FAQ is NOT about DV. DV work is still in progress, and there are no perfect TV’s or external devic…

The more details you give us about your hardware, network, media, the more the 4K people can help you get there.

[dextose]

So I found this topic 4K buffering on Samsung 8 series, and it looks like it’s the same problem I have. If I play a film with DTS 7.1 Plex will transecode it. But if I play the same film with DTS 5.1 or AC3 Plex will direct play both video and audio, and there is no buffering.

I have tested it on the same files and a few others, and it appears to be working as long as I skip DTS 7.1…