Apple TV 4K Gen 2 (2021) visual stutter on 4K HEVC files

Server Version#: 1.45.0.3013-1676042f
Player Version#: 8.3 (2621)

This is driving me crazy!

I have noticed that all of my 4K HEVC MKV files that are played via my Apple TV 4K 2nd Generation (2021) have a slight stutter to them. About every 10 or 15 seconds a see a very slight hiccup and then it continues to play as normal. This is especially noticeable in scenes with a smooth camera pan.

I activated the debug display, but no dropped frames are reported. I have confirmed the files are good with other plex clients and other players on my PC and do not show the stutter. I have compared the same file on other Plex clients (including the built in Smart TV player on the TV the Apple TV is hooked up too!) and the stutter seems to be exclusive to the Apple TV client. I even had other people in my household take another look at it to make sure I wasn’t seeing things, and now they can’t unsee it while we movies.

Am I the only one? Is this a known issue? Any fixes?

2 Likes

Having the exact same issue also with 4K HEVC files. Didn’t have this issue before.

Here is the video info:

  • Codec HEVC

  • Bitrate 15360 kbps

  • Language English

  • Language Tag en

  • Bit Depth 10

  • Chroma Location left

  • Chroma Subsampling 4:2:0

  • Coded Height 2160

  • Coded Width 3840

  • Color Primaries bt2020

  • Color Range tv

  • Color Space bt2020nc

  • Color Trc smpte2084

  • Frame Rate 24 fps

  • Height 2160

  • Level 5.0

  • Profile main 10

  • Ref Frames 1

  • Width 3840

  • Display Title 4K HDR10 (HEVC Main 10)

  • Extended Display Title 4K HDR10 (HEVC Main 10)

  • Codec EAC3

  • Channels 6

  • Bitrate 768 kbps

  • Language English

  • Language Tag en

  • Audio Channel Layout 5.1(side)

  • Sampling Rate 48000 Hz

  • Display Title English (EAC3 5.1)

  • Extended Display Title English (EAC3 5.1)

  • Codec SRT

  • Language English

  • Language Tag en

  • Display Title English (SRT)

  • Extended Display Title English (SRT)

  • Codec SRT

  • Language English

  • Language Tag en

  • Display Title English (SRT)

  • Extended Display Title English (SRT)

Need more info. Is there any possibility this is judder?

Our TV Motion Tests: 24p Judder - RTINGS.com

Is the Apple TV set to Match Frame Rate?

Turn on Match Dynamic Range or Match Frame Rate on your Apple TV - Apple Support

It’s pretty common for downloaded files to be poorly constructed, and to have inconsistent timestamps between the video streams and the container.

Sometimes disabling Direct Play in the Plex app is enough to address this, because Plex will extract the video stream and put it into a new container on the fly.

Can either of you share a recording of what the problem looks like?

Can you share a sample file or link to a file?

I don’t think it’s judder. I have a Sony X900H and use an Apple TV 4K. Playing the exact same file through Infuse doesn’t have any issues. It looks like the playback is dropping frames every so often. I have the Apple TV 4K hardwired through ethernet to the server so there isn’t any bandwidth limitations. Playing the same file on the official Plex iOS app and and on macOS also don’t have any issues.

I’ve turned on both the Match Dynamic Range and Match Frame Rate settings on the Apple TV - both have no effect.

I’ve also tried to disable Direct Play - but the video plays the exact same way through Direct Stream.

Here is a link to a sample: Link

Here is a link to a recording showing the playback: Link

It almost looks like the video recording has a glitch every few seconds - but this is the stutter and it’s very noticeable in person.

Agreed, doesn’t look like judder.

Grabbing the sample, thanks. I can look more closely later.

Have the exact same problem with the same type of files, can confirm it also happens with appletv 4k gen 1. Files plays fine in infuse or MrMc on same appletv. Hope we can get to fix this asap, it is very noticeable in person.

I’m having the same issues on any high bitrate 4K HEVC files on Apple TV. Same files play fine in Infuse, on a Mac or windows PC and on my PS5.

I’ve tried the following to no avail:

  • Disable Direct Play (Direct Stream instead)
  • Disable match framerate
  • use old video player
  • use plex beta for apple TV

To follow up on this… I also noticed the same stuttering even when the built-in screen saver is playing. Changing the TV’s motion or clarity settings didn’t seem to have any impact on this.

Anybody else seeing the same thing?

@Volts any findings from the sample?

!!

That’s very very interesting. Do you have the ability to test connecting the ATV to a different TV or to a monitor? Many monitors have HDMI.

No actually. It looks fine to me. I was expecting to say there was a muxing or timestamp issue.

Did some more tests today.

A restart got rid of the screen saver stuttering.

Turning off Match Content in the ATV setting didn’t fix anything.

However, if I force the Plex app into SDR with the Display Type setting, it seems to playback content without stuttering - but with SDR colours.

I tried some other 4K HDR encodes that don’t have an issue.
Here is a sample that doesn’t stutter: Link

Anything in this file that’s different?

Unfortunately don’t have anything to plug the ATV into…

There definitely seems to have been a recent change in the encoding that a specific service uses that is no longer fully compatible with the ATV.

Like the old reference frame issue that was a damn plague, hopefully this can be worked out and incorporated into the playback engine too.

Yes! and because of the popularity of this specific service I hope this can be revised asap!

I don’t have a (2021) ATV at the moment to test.

Has anybody tried muxing a video with MP4Box and -inter 120 and possibly even -tight?

Prompted by @mpiva on another thread. They suggested it helped with playback on another device.

normal appletv 4k (gen1) also have this problem. Same video plays flawless in infuse and mrmc

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