Can't stream audio via Airplay to Denon X4000 receiver
I have a late 2013 Macbook Pro with 13-inch Retina Display. It came preloaded with Mavericks. I'm trying to stream audio via airplay to my Denon X4000 receiver which is airplay certified. For some reason airplay only works with iTunes. If I go into the sound preferences in Mac OS X my Denon X4000 receiver is listed as an audio output device but OS X won't let me click on it. It immediately reverts back to the laptop's internal speakers. I just recently started having this problem as of tonight when I tried to listen to music from Google Play Music. Has Apple decided to force iTunes down everybody's throat? How do I fix this?
MacBook Pro with Retina display, OS X Mavericks (10.9)