I followed these steps to install Shairport on Raspbian
http://jtech4you.com/how-to-setup-a-raspberry-pi-airplay-receiver/
and it works fine, except one thing: after a while (the next day), my iPhone does not detect the AirPlay option anymore.
If I connect to Shairport form my PC, using TuneBlade (which has no problem detecting it), this seems to bring it 'back to life' and the iPhone sees it again.
The PI is connected to the network using a WiFi dongle.
Do you have a clue on what's going on and what could be done to prevent this?