So I have my AirPort Express hooked up in my kitchen to a sound system. As of late, the Express has been dropping from my network with a solid amber light. Usually, I would unplug and replug it in and it would connect to my home network so I can AirPlay from my computer again.
After updating to the new iTunes, I had to fix it once again with the unplug replug method, but I also had to modify my firewall settings on my computer with the new iTunes. I had to change it through Windows Firewall and have it function on the UDP Protocol. After that, it started working again
Yesterday, I wasn't able to connect at all to AirPlay. The Express's light was solid amber, so I unplugged replugged. Wasn't able to connect at all, even with a solid green light.
I downgraded iTunes to 10.7, I restored the AirPort Express to factory default and restarted again. AirPort Utility recognizes the device and I'm able to configure it, but I'm not able to AirPlay through it with my computer, however my iPad and iPhones are able to.