First ATEM Mini Pro stream! + Apple vs VP9

Just did my first stream with the ATEM Mini Pro today!

Overall it went well... forgot to record to USB drive which was a bummer...

If you wanna see it, here it is:
https://www.facebook.com/UlfDeWolf/vide ... 783324605/

Now to the weird part. It seems like Facebook is using VP9 for their 720p (which they call HD) videos that remain on Facebook after a live stream. As Apple isn't supporting VP9, they can only be seen in 360p. But using Firefox, for example, HD is available.
And the worst thing: When a view the video now using Safari or the Facebook app on my iPhone, the audio is out of sync with the video!!! But if I look at the video using Firefox I get both 720p and it's in sync.
Anyone else experienced this?
Looking at other livestreams (that are not live anymore but remain on FB) they are in sync. Why not mine???

Can someone else using Safari/iPhone confirm it;s out of sync for you as well?
And see if it's in sync on other browsers / Android phone?

Yes, it's out of sync in Safari, but in sync with Chrome.

Yes, it's out of sync in Safari, but in sync with Chrome.

Thanks for checking... So damn weird.
I wonder if it's because we used 25p and Facebook wants 30p? But why is the VP9 (I'm speculating there) feed in sync and how did they mess up the low res H.264 (I assume) feed??

Checked on Mac notebook and Windows 10 PC.

Mac Notebook, Safari has delay, Chrome no obvious delay
Win 10 PC, Chrome no obvious delay, MS Edge browser, no obvious delay.

Thanks for checking. So seems like my theory is correct in that it’s only Mac/Safari and the Facebook app on iPhones...