60 fps video playback stutters on Apple TV 4K

[robogirl]

Hi!
My ATV (4K, 1st gen, tvOS 17.1) jitters when playing back 1080p@60 fps content in specific cases, such as playing videos through Home Sharing and Twitch VODs — but not Twitch streams or YouTube videos, for instance.
This problem is easiest to reproduce when ATV's resolution is set to 4K, and happens less/the jitter is shorter when set at 1080p. Display settings such as range/framerate matching, chroma subsampling modes, switching between 59.96/60 Hz, or even wireless audio sync don't seem to affect this behaviour. Dynamic range is permanently set to SDR.

I'm sure this issue is not due to HDMI/TV because:
1) again, the ATV doesn't have a problem with 1080@60 fps content in more typical cases
2) the UI remains fluid
Still, this happens on both TVs I've tried: Samsung AU8000 and a random JVC, using an HDMI 2.0-compatible cable.

Here's an example recorded through QuickTime on a Mac, jitter starts at 20 seconds:

(sample video here)

In general seems related to this issue, though I believe it's not caused by the Twitch app, but rather some sort of bug in ATV's playback backend

 

[kristoffer4]

Yes, my Apple TV 4K 1. Gen did the same. It went away with the update to the latest Apple TV.

 

[stockseer]

Looks fairly typical from buffering/jitter related to internet connection or speed; not the computer or software. (I had similar until not just fiber gigaspeed internet but a new gateway modem... which supports WiFi6. So anyway my 2 cents; check your thruput..

 

[robogirl]

Yes, my Apple TV 4K 1. Gen did the same. It went away with the update to the latest Apple TV.

I really hoped the latest update would finally fix this, this issue is annoying me a lot — but it didn't. I'm on tvOS 17.1. Two people in the reddit issue I linked also say that the update didn't help.

Looks fairly typical from buffering/jitter related to internet connection or speed; not the computer or software. (I had similar until not just fiber gigaspeed internet but a new gateway modem... which supports WiFi6. So anyway my 2 cents; check your thruput..

Thanks, but buffering looks different on ATV. Also, much heftier files play fine, as long as they are the typical 30 fps or less.

 

[robogirl]

Update: this happens when watching regular Twitch streams as well, but like... way later. I hate Apple 😒