Hello, it seems that Apple has removed the ability to send audio from one Apple TV to another. Can someone confirm this? I've used this feature to send the audio from Apple TV to my stereo system. The removal of this function has been extremely unfortunate and negatively impacted my experience.
They removed that option through the Settings/Video and Audio/Default Audio Output menu.
You can still use it if you hold the “Home” button on your remote, the one that looks like a TV, a pop up menu will appear on screen and on the bottom left you can select your AirPlay device. You will have to that every time your turn your AppleTV on.
If you want the feature like it was before, drop a comment on Apple’s feedback site.
Apple TV to Apple TV Airplay
