So I actually got mine fixed yesterday, I had to reboot all of my networking equipment. Unplug everything that manages the flow of traffic and then unplug the receiver. Reboot in this order (waiting 30 seconds between each) Modem first > router > switch 1 > switch 2 > etc. > Receiver. After powering everything back on, AirPlay worked right from the get go for me.
My personal opinion on what happened is that the receiver grabs an IP address and then doesn't let go even though that particular address lease may have been released on the router side.