HTML5 video playback issues on Mac Studio M2 Ultra with Tahoe 26.0.1

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Level 2

357 points

HTML5 video playback issues on Mac Studio M2 Ultra with Tahoe 26.0.1

I have a Mac Studio M2 Ultra with Tahoe 26.0.1.

Everything in Tahoe was fine for a few days until suddenly any site with HTML5 video would fail to play back video. (ie YouTube and basically any streaming site).

When you click play it would just spin forever and then YouTube would throw up an alert saying "If playback doesn't begin shortly, try restarting your device". I restarted, and it doesn't fix it.

Other things I've tried, to no success…

(1) Cleared Safari cache

(2) Tried Chrome instead of Safari

(3) Created an new user account

Also, I can completely rule out a network issue! I tried running my own portfolio website locally in Safari and Chrome and the HMTL5 video does not playback! These mp4 files play back just fine in Finder.

The only thing that fixed it was booting into Recovery mode and reinstalling macOS Tahoe over top of my existing installation. Nothing is wiped during this process, but every system component is replaced. It's like a deep OS level component got corrupted at some point?

I thought that was the end of it, until today it started happening again!

Playback is fine on my other updated devices (M2 MacBook Air with 26.0.1, iPad Pro with 26.0.1) but I don't use those as much so I don't have a true comparison.

This is incredibly frustrating. I can't be reinstalling Tahoe every couple of days! :(

[Edited by Moderator]

Original Title: HTML5 video playback (YouTube and other streaming sites) keeps breaking in Tahoe. Even affects local websites (ie NOT a network issue)

Mac Studio, macOS 26.0

Posted on Oct 11, 2025 10:18 AM

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Answer 1

Top-ranking reply

Huw Williams

Level 1

22 points

Dec 13, 2025 4:52 AM in response to Mark Paterson

I've been having the same problem here, and found your posting on reddit which concludes with the solution around the virtual audio driver. I checked my system and there was no such virtual driver, but I do listen through a dongle dac, so I unplugged that and bingo! problem solved. Clearly its the audio upsetting the 'apple' cart, but it is a strange one. Hope this helps!

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Answer 2

Oct 11, 2025 10:28 AM in response to Mark Paterson

This begs question: what may be different in the affected mac? Please run Etrecheck and post its full report here.

Use the “additional text” button and paste the report into the text box.

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Answer 3

Mark Paterson Author

Level 2

357 points

Oct 11, 2025 1:39 PM in response to Mark Paterson

I’ve set up an hourly monitoring script that computes MD5 checksums of all video frameworks and caches, and logs any changes along with GPU/video decoding services and all LaunchAgents/Daemons, creating a new timestamped log each run. It also sends a macOS notification if anything changes. This way, I can capture exactly which file or process causes the HTML5 video playback to break when the issue reoccurs.

All is fine right now, but as soon as it stops working again hopefully I will have a better idea what is causing the issue.

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Answer 4

Mark Paterson Author

Level 2

357 points

Oct 16, 2025 10:21 PM in response to Mark Paterson

It's much MUCH worse than I thought.

After a couple days with no issues, I needed to reboot. After restarting I immediately saw that not only was the problem back (YouTube once again failed to play) but it actually affects almost ALL MEDIA, not just HTML5 web video. MP4 files do not play LOCALLY (either through QuickLook, QuickTime, IINA, etc), MP3 and M4A audio files do not play back. Weirdly, the only files I've found that can actually play back ok are HEVC encoded MOV or MP4, or ProRes MOV.

My script to monitor MD5 checksums found no corruption in between the last time it all worked and after, so I'm really out of ideas.

The only fix is to re-install Tahoe. I refuse to re-install Tahoe for a 3rd time just to have this work for a couple more days. I'm done. I'm rolling back tonight. I'm so ****** off.

It's not even the only issue I've seen. Spotlight is completely broken. I can find files in Finder but nothing shows in Spotlight.

What a total disaster.

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Answer 5

Mark Paterson Author

Level 2

357 points

Oct 11, 2025 11:41 AM in response to BobTheFisherman

Well whatever, I don't want to get into a back and forth about the virtues of said software. I'm just interested if anybody else is experiencing this HTML5 video issue.

I once again just re-installed Tahoe over top of the existing system and lo and behold, HTML5 video is working again. Like I said previously, this appears to be the only fix!

For what it's worth, I've filed a bug report with Apple.

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Answer 6

Mark Paterson Author

Level 2

357 points

Oct 11, 2025 4:41 PM in response to Luis Sequeira1

I've been a pro Mac user for 25+ years and I've never heard of Etrecheck. I just googled it and I would rather not install that software as it seems like malware and is incredibly intrusive.

[Edited by Moderator]

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Answer 7

Oct 16, 2025 11:50 PM in response to Mark Paterson

You are experiencing severe problems that the overwhelming majority of users are not seeing.

It seems pretty obvious that these problems are caused by something peculiar to your system.

You were very sensibly advised to run a diagnostic program, but refused to.

And yet you have no qualms installing whatever is actually causing you problems.

We have no access to your system and have no idea what stuff you have installed unless you tell us.

If you keep waiting for a fix, you are likely to be disappointed and frustrating.

Playing html 5 video is something that millions do every day. You can imagine the outcry if the horrible issues you are facing were experienced by even a few dozen people, let alone millions...

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Answer 8

Oct 11, 2025 11:34 AM in response to Mark Paterson

Thousands of users here would disagree with you and your assessment of Etrecheck.

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