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)