Q: AirPlay Icon not showing

I cannot get the AirPlay icons to show on my iPhone 5, iPad Air or computer using iTunes (11.1.5.5) with my new AppleTV.

• AirPlay on AppleTV is turned on
• All device software is up to date
• Home Sharing is on
• All Apple accounts are the same on all devices
• All devices are using the same wifi
• All devices have been rebooted including the router

The iPhone, iPad and computer are all USA products.  AppleTV was purchased in the UK.  Could this be the problem?

Thanks.