If you haven’t already you can activate AirPlay on your old Apple TV 2 – just look here http://www.remotehd.com/AppleTV/Overview
Anyways – one thing I did find annoying that the AirPlay name is “Apple TV-RHD”, and I wanted to be able to customize it to something more appropriate, like “Bedroom” or “Patio”. I have not solved the problem completely yet as even though I can set a custom name, it still suffixes it with “-RHD”.
1. SSH to your AppleTV (usually appletv.local), I use CyberDuck on Mac to be able to copy/replace files via a GUI.
2. Download the file /etc/rc.common to your Mac/PC
3. Add the following line to the bottom of the file replacing ‘Bedroom’ with whatever you want it to be:
sudo -u frontrow defaults write com.apple.frontrow "UserDeviceName" 'Bedroom'
4. Copy the file back to your Apple TV, and be sure to set the permissions to allow execution of the script
chmod +x /etc/rc.common
5. Reboot your AppleTV and enjoy your (almost) custom AirPlay name.
I’ll work on getting rid of the “-RHD” but looks like it may need to be some hex editing fun 
Darran Boyd 