There’s 3 likely areas based on the info you provided, and it is kind of all over the place, but I’m thinking: Network health, GPU and sound card (yes, actually the sound card because it is pivitol in timing the video. Windows relies on the sound cards clock to sync video to, and has since Windows NT/9x).
First, try enabling stats for nerds, and screenshotting it. This is the network side:
If that’s the case, might want to head to speedtest.net and not just check the speed, but the ping and jitter (as that can contribute).
BUT, you did say this:
Which actually points to something very old school with AV syncing so you know, audio doesn’t lose sync with the video. IF when muted it works, and unmuting it breaks it, it might actually be a sound card driver. Shockingly yes.
For example, my sound card has intensely high sampling rates such as 384KHz. IF I use those, then actually, I can get random video freezes when unmuted. If I select 192KHz, it goes away. It’s a sync/timing issue problem and the video is pausing because it failed to actually sync.
If your sound card doesn’t even go higher than 192KHz then great, maybe it’s just a driver update then.
But then there’s the GPU angle here that was mentioned as well:
brave://gpu
Let’s ensure it’s actually in good standing. This should be all we need to verify is that you have a good amount of green, especially on video decoding for hardware acceleration.
(Don’t worry if Skia Graphite is disabled for you, that’s the default, I only intentionally enabled that one).
Beyond this, you did mention Chrome, but not specifically if Chrome had the issue or not. Does Google Chrome also do the same thing, or is it actually working just fine? Because if Google Chrome is working just fine, then all of the above is null and void and not related.