I had similar issue. I figured out in the end it was related to my Time Capsule - 802.11ac. The fix was to give the 5Ghz network a separate SSID instead of having both 2.4GHz and 5Ghz advertise the same SSID name. Airplay was also messed up because of this problem between non Apple Airplay compatible devices and Macs, iPhone and iPad. This solved my problem for Macs, iPhones, however both my iPad Air and iPad 4's are still messed up and get see entire Airplay network.