Bug 236779 – REGRESSION: Video stutters and crackly sound on STP 140

• Status: REOPENED
• Component: Media

[Jack Wellborn]

Hello,

I have noticed that with STP 140 that video elements stutter and sound crackles. I suspect this was happening before release 140, but I had assumed it was an issue with my Bluetooth headset rather than Safari. It was only today that I happened to notice the issue occur with the computer's speakers. I do not have this issue with blue Safari.

System Info:
macOS 12.2.1 (21D62)
MacBook Pro (16-inch, 2021) with Apple M1 Pro and 32 gigs of RAM.


Reproduction Steps:
1. In STP 140, go to https://www.w3.org/2010/05/video/mediaevents.html
2. Click "play()"

Expected:
Video plays smoothly and with clear sound.

Actual:
Video stutters and sound crackles.

[Radar WebKit Bug Importer]

<rdar://problem/89180854>

[Alexey Proskuryakov]

FWIW, I could not reproduce this (same hardware, somewhat newer software).

[Jack Wellborn]

Based on Alexey's inability to reproduce, I restarted my MacBook Pro. Not only did the issue seem to go away, STP seemed to be in state where it was not quitting until I force quit. Given these observations, I suspect my STP was in some weird state. I think we can close for now, and I will reopen if the behavior returns. Thanks for your time.

[Chris Dumez]

Thank you for following up.

[Jack Wellborn]

Created attachment 452874 [details]
Demonstration of Choppy Video/Audio in STP 140

[Jack Wellborn]

So I found a more reproducible scenario. First of all, the issue does seem more prevalent with Bluetooth headphones. Second, it seems like it could be related to repainting(?) I have attached a video exhibiting the behavior. The first browser is STP 140. The video plays okay to start, but starts stuttering when I move the cursor. The second browser is blue Safari and plays fine regardless. Note: You will have to crank the volume when listening to this. I had to an EarPods mic inside my AirPods Max to capture the sound. Hope this helps.

[Jack Wellborn]

I have confirmed that the issue persists in Release 141. Even after a restart, YouTube stutters while wearing AirPods Max. As with before, the behavior does not occur in blue Safari.

[youenn fablet]

(In reply to Jack Wellborn from comment #7)
> I have confirmed that the issue persists in Release 141. Even after a
> restart, YouTube stutters while wearing AirPods Max. As with before, the
> behavior does not occur in blue Safari.

Could you provide a sysdiagnose and send it privately ([e-mail])?

[youenn fablet]

(In reply to youenn fablet from comment #8)
> (In reply to Jack Wellborn from comment #7)
> > I have confirmed that the issue persists in Release 141. Even after a
> > restart, YouTube stutters while wearing AirPods Max. As with before, the
> > behavior does not occur in blue Safari.
> 
> Could you provide a sysdiagnose and send it privately ([e-mail])?

Ideally with time of reproduction (and the steps you did to reproduce the issue).

[Jack Wellborn]

Hi Youenn,

I am currently sending the sysdiagnose as requested along with some more reproduction steps. For convenience sake, I am also adding those same reproduction steps here.

(With AirPods)
1. Close out of all applications.
2. Open just STP and navigate to https://www.youtube.com/watch?v=x7qPAY9JqE4
3. Play the video. For me the starts playing smoothly.
4. Start opening other applications. For me, opening Slack, Music, and the App Store started causing the issue. (Coincidentally, running sysdiagnose really made it happen.)

Thanks,

~Jack

[Jack Wellborn]

After updated to macOS 12.3 yesterday, I haven't been able to reproduce. I will resolve again and reopen if the issue re-emerges.

[Jack Wellborn]

Hello all,

This bug has returned with STP 169 and macOS 13.3.1 (a) (22E772610a). Let me know what y'all need. 

Thanks,

~Jack Wellborn