iTunes 12.2’s AirPlay button goes away when Beats 1 is on, but there’s a way to stream it to your AirPlay sound output.
The AirPlay button in iTunes 12.2 disappears as soon as you connect to Beats 1, the new radio station that’s been launched as part of the new Apple Music service. If you’re accustomed to streaming music from your Mac to an AirPlay music source like AirPlay-equipped speakers, an Apple TV or an AirPort Express connected to a speaker system, this looks like a deal-breaker. But it’s not.
This looks like a really weird bug that I hope Apple will patch quickly in a forthcoming iTunes update. But until then, this is a fairly easy workaround. Just bear in mind that this sends all of your Mac’s audio to your AirPlay speaker, not just iTunes.
First of all, if you’ve already told your Mac to send audio output to an AirPlay source, it’ll continue to send the Beats 1 audio there, like this:
Alternately, you can give this shortcut a try
How to send Mac audio to AirPlay speakers