I recently bought an airport express so I could use AirTunes to hook up multiple speakers to my computer. I don't have an internet connection, but you aren't supposed to need one in order to use AirTunes it says. Anyway, I set up the AirPort, plugged it in, connected the speakers, and installed the Airport Utility, however, when I hit "scan" in the airport utility, nothing shows up. What do I do?