Cannot connect Apple TV to computer music library
2015 Mac
10.10.1 Yosemite
Updated iTunes
Updated Apple TV 2 software
same network
New router connected to Time Capsule, but everything else works.
Mac Pro
The following article(s) may help you.
Troubleshooting Wi-Fi networks and connections
Wifi Diagnostic Software (for Mac users)
You may also find some help on this page, where I’ve collected some of the more unusual solutions to network issues.
When making adjustments to your network for better optimisation, you may find some of the points mentioned on this page helpful.