Has anyone successfully gotten wi-fi sync to work with their iPhone 5 and iTunes in Windows 7? I never really used it with my iPhone 4, but had gotten it to work once. I've enabled it on my phone, restarted iTunes, restarted the computer, restarted the Apple Mobile Device service, disabled the firewall. No matter what, the "Sync Now" button stays grayed out on the phone, it says "Sync will resume when [system] is available", and the phone never displays in the left pane of iTunes.