Video stuttering since version 8.18 of the Apple TV app

Plex Players Streaming Devices
81

I found an H.264 encoded file that is also stuttering so as previously mentioned, this isn’t the issue. That being said I do have some videos that do play fine without stuttering. I was wondering if anyone else has found any videos that do not stutter. It may be worth comparing some of the details to determine if there are any common factors such as bitrate, size of file, etc.

82

I had bought an Apple TV expecting better Plex performance - interestingly, the Plex App for my 5 year old Samsung The Frame TV (Tizen OS based) is much better: Less pretty but plays just everything I throw at it - even video files where the Plex App on Apple TV crashes.
Very disappointing to be honest!

83

I read in another thread that someone fixed it by switching to the old audio engine. Gave it a go and all stuttering stopped for me instantly.

84

Hi folks, I am wanting to dig in and understand this issue more so our developers can hopefully find a fix to this long standing issue. (I also came across a reddit post about it as well in my quick search about playback issues on Appel TV → (Reddit - Dive into anything)

I myself tend to watch a lot of 1080p content on my 2022 4K Apple TV, and some 4K HDR remuxes I have made myself, and don’t see a noticeable stuttering issues. What I want to do is find out what is different about my setup so I can reproduce what many folk here are seeing.

Here is how I have things setup in my living room;

Apple TV 4K (2022 with Gigabit ethernet) connected directly to LG CX OLED TV, then eARC to an LG SP11RA soundbar.

  • Apple TV Settings:
    • Format = 4K SDR
    • HDMI Output = YCbCr
    • Chroma = 4:4:4
    • Match Content = Range & Frame rate
    • Audio Format = Auto, Atmos Available
  • Plex Settings
    • Use old video player = Off
    • Use old audio engine = Off

My test files are;

  • The Hobbit: An Unexpected Journey (54Mbps) Remux
  • Back to The Future II (93.4Mbps) Remux

Both are HEVC and play without stutter (I skipped to a few large panning shots and it plays smoothly).

To be clear I am not disputing that there is an issue, but rather showing that for some (like myself) it works correctly. My aim is to get to the bottom of why it doesn’t for those affected folk here. What I need from you is info on how you have your device setup, and what content you are playing that causes stuttering and dropped frames etc. The more details the better!

85

Apple TV 4K (2022 with Gigabit ethernet) connected directly to Samsung Q70R QLED TV then ARC to an Samsung HW-N650 soundbar.

  • Apple TV Settings:
    • Format = 4K SDR
    • HDMI Output = YCbCr
    • Chroma = 4:4:4
    • Match Content = Range & Frame rate
    • Audio Format = Auto
  • Plex Settings
    • Use old video player = Off
    • Use old audio engine = Off

Happens on all files from low to high bitrate and SD to 4K. Is not like traditional stutter or judder the motion is not smooth and it happens all the time. If I reconnect my 2021 Apple tv 4k back onto this TV with identical settings everything is perfect. Switching back to the old audio engine seems to help matters as does turning subtitles on then back off again at start of playback.

1 Like
86

Same for me, same settings etc. I also believe that the old audio engine has been better but yeah this issue happens on all files. It’s a micro stutter and it doesn’t happen consistently in the same spot, if I rewind it will occur in slightly different places.

2 Likes
87

I wonder if the issue gets masked by my OLED TV’s motion settings? I will try turning those off tomorrow and doing some more testing. In the meantime do you have details about content you are playing? perhaps you could upload a sample that is known bad for you, so I can test on my side.

I believe we are planning to update MPV (the video player engine we use) in the near future. This may resolve the issue, bit I first want to reproduce it so we can better understand it.

88

I don’t have any sample files handy but it’s literally every file that I try. Others have said it’s immediately apparent going between build 8.17 and 8.18 I wonder if you can see any difference between those on your end?

89

Hi,

Could you also give your thoughts on this one as well ?

https://www.reddit.com/r/PleX/comments/16bfztm/apple_tv_plex_users_test_this/

Google Drive Link
https://drive.google.com/drive/folders/1X_338_UFJVstXxx49vFOsy7vOFz4GZgZ?usp=sharing

Apple TV 4K 2021

  • Apple TV Settings:
    • Format = 4K SDR
    • HDMI Output = YCbCr
    • Chroma = 4:4:4
    • Match Content = Range & Frame rate
    • Audio Format = Auto
  • Plex Settings
    • Use old video player = Off
    • Use old audio engine = Off

Apple TV 4K 2021 TVOS16.6

  • Apple TV Settings:
    • Format = 1080p SDR
    • HDMI Output = YCbCr
    • Match Content = Range & Frame rate
    • Audio Format = Auto, Atmos Not Available
  • Plex Settings
    • Use old video player = Off
    • Use old audio engine = Off

iPhone 13 Pro Max
iPad Pro 12.9 5th Gen
Macbook Pro M1 Pro (also encounters the issues, but they go away if i disable Use Hardware Decoding)

All with the same outcome, i am the thread starter of that reddit thread, do test it out or escalate it to the relevant team.

And i would say most of the times i dont have an issue with playback on Plex but there have been a number of times that i do, in fact i encountered a new one today. Its not an issue with bitrate or file size or even the presence or absence of HDR or DV. I too have tested with huge remuxes and it played perfectly fine, i want to understand why some times there are issues.

I have a 10G connection from my server to router and obviously 1G to the Apple TV, everything is wired and my connection is great.

Edit : Added 2 more video files in that G drive link on reddit.

90

Thanks for looking into it. This is how I described my experience in April near the top of the thread:

I tried to troubleshoot it a bit, but it was a little hard to a consistent pattern. It seems it happens a lot more frequently for me with Blu-ray rips (both UHD and HD) that contain DTS-HD tracks, but not exclusively. All files I ripped myself. But, it’s happened a bit if I select a .ac3 track from a rip instead, though maybe less frequently. But, it happens every 10-40 seconds or so, with almost every file I tried, wired or wireless, HD or 4K, SDR or HDR. One film played back perfectly of the 10 or so I tested, which was a Blu-ray rip with a mono PCM track. I have found consistently though that if I make the Plex app transcode it doesn’t happen, even if I transcode the audio (ie. TrueHD tracks transcoded to FLAC don’t have this issue for me, even with video not transcoding at all).

The debug screen didn’t show any dropped frames, and it doesn’t stutter like a bandwidth issue (plus one of my ATVs is wired with gigabit on a fast network, the other is on wifi but is fairly close with a very strong signal on a wifi 6 network). I usually use Infuse, so I’ll switch back to that for now and hopefully try the official app out again when there is another update.

My files are all generally .mkv files that I ripped myself in MakeMKV from 1080p and 4K Blu-rays, so a mix of H.264 and HEVC. I find it is much more likely to happen if I watch something that is partially watched in Continue Watching, and less likely if I am starting a movie from scratch. It’s easier to spot if I watch something with long pans or dolly shots or dancing. In my case it is not limited to any particular files — it will happen with any Blu-ray rip, especially those with a bit of a higher bitrate and DTS-HD audio (since that doesn’t need to transcode). It will look sort of like a dropped frame, or kind of the way a PAL file poorly converted to 29.97 NTSC can sometimes look where it drops or repeats a frame.

I have two AppleTV 2022 4Ks — one connected directly to a Samsung TV with no soundbar or AVR, and one connected to an LG C3 directly and then eARC to a Sennheiser Ambeo soundbar. Back in April I had a LG C7 OLED and the AppleTV 2022 4K was connected directly to the soundbar instead of the TV. I see it on both, and notice it a bit more on the OLED. It’s also seemed slightly less frequent in recent updates to me at least.

91

Thanks for that, I’ll check the code commits between those two releases to see what changes might have affected this.

92

I greatly appreciate the detailed response here and I’m sorry I haven’t jumped in sooner to help address this issue. I’ll grab the samples and do some testing. I really want to reproduce this as it will better help me work with our developers to debug and fix the issue.

2 Likes
93

This makes me think it has something todo with frame rate and handing audio packets when we are direct playing. Thst would line up with why it doesn’t happen (or maybe not as often) when we transcode TrueHD to FLAC etc

This is a helpful bit of info. Do you have some example movie titles that you see it evident on?

What settings do you have on your LG for the input you are using for the AppleTV? Could you take some photos of the picture mode and any motion setting so you have enabled? Also is audio for that input set to pass through or bitstream or auto?

94

Thanks for looking into this! I noticed it the most on my Blu-ray rips of The East and The Worst Person in the World. And UHD rips of Phantom Thread and The Shape of Water. The first two are shot handheld, so I think it jumps out more in them since there is more constant motion in the frame.

Also, files that direct play in the AVPlayer don’t exhibit this at all in my experience.

FWIW, I was in that small group of testers that had the new audio engine flagged on before the broader release and I started to notice it around that time (though totally realize it might not be directly related to that).

My LG settings are Cinema Home or the ISF preset for SDR, with all the motion settings turned off except True Cinema. I also use Infuse and don’t see this issue there, or on my Shield in Plex with the same settings on that input.

Thanks!

95

Thanks for taking ownership of this issue. Here is my setup:

Apple TV 4K 2022 connected with Gigabit ethernet and connected directly to Denon S660H AV Receiver then connected to Samsung 4K QN85B Neo QLED

  • Apple TV Settings:
    • Format = 4K SDR
    • HDMI Output = YCbCr
    • Chroma = 4:4:4
    • Match Content = Range & Frame rate
    • Audio Format = Auto, Atmos Available
  • Plex Settings
    • Use old video player = Off
    • Use old audio engine = Off

I have experienced stuttering on 1080p and 4k HDR videos. Based on the post right before yours I changed the Use Old Audio Engine to “On” and noticed that the video stuttering went away. I haven’t done much testing but at least for the video I was watching last night, there was stuttering until I changed that setting. Hope this helps.

2 Likes
96

I did 2 videos a day after the post. new test 2.mkv is actually a weird one; it actually plays fine on my phone and ipad but not on the apple tv.

97

I would agree with others that the visuals of the issue look somewhat like pulldown judder when framerates aren’t quite right. It’s not like buffering or slowmo, it’s like a micro-stutter that could be repeated frames or something of that nature. That’s why it is most apparent on panning shots. Obviously I’ve tried forcing various refresh rates and stuff, as well as toggling the auto framerate match, and none of those things seemed to help.

2 Likes
98

I agree with that description of the problem. Also, using the Old Audio Engine doesn’t seem to fix the problem. At first it seemed to solve it but the stuttering returned after starting a new video. I did notice that turning on subtitles seems to reduce or eliminate the stuttering.

99

Here’s some details on the video file that is giving me issues:
image

100

Set up my new Apple TV 2022 last week and immediately noticed those micro-stutters too. Doesn’t seem to affect all movies tough but did only test a hand full. Super annoying :frowning: