Airplay broken after update to 10.11.2

Hi all,

Today, I have updated my iMac late 2013 27" and also my wife's MacBook Pro 2014 13" to El Capitan 10.11.2. Suddenly, on both devices we have lost ability to use Airplay! It will not get shown in iTunes and Beamer app won't find it as well. It was all working well until I had Yosemite 10.10.5. We have Apple TV 4th Gen. All updates installed. Tried restarts, disabling Firewall. Does anyone have the same problem? Is there any way to fix it besides downgrading back to Yosemite? I have backup on Time Machine but my wife doesn't.

The strangest thing is that on her MacBook Pro I can connect to Apple TV display and I can stream from Youtube. On my iMac I can't do this at all. Connecting from iPhone 6 Plus with iOS 9.2 works just fine.

We are using latest gen of Airport Extreme. It shows Apple TV as connected.