Hi!
I can play and stream anything from NAS or Spotify via WiFi, but when I try to AirPlay from my Mac (latest official 10.11.6), iPhone or iPad (both on latest dev betas, but the behaviour was the same on official 9.3.4), I get 1-2s of audio followed by a crackle and then the sound stops completely. Monkeying with buffer size doesn’t seem to have any influence. I have no way to try out wired connection ATM.
TLDR - AirPlay via WiFi results in audio stopping after 2s
What to do?
I know for sure that airplay demands almost-perfect network conditions when operated via wi-fi… Your best bet is to get as near as possible to your router or improve your wireless network connectivity… Could you detail your wireless network configuration (distance to router, band, etc… ) ?
I got the same problem if I want to stream something over Airplay. My Pi is connected over LAN and the distance between my phone and the Fritzbox 6490 is not more than 5 meters without any obstacles inbetween.