Photostream and WiFi not working after 5.1.1 update

Since updating to 5.1.1 my Apple TV won't detect any WiFi and Photostream refuses to connect to 'the server'. My iPhone, iPad and Mac Mini all connect to the WiFi network without difficulty, and Photostream works perfectly amongst those three pieces of kit. The Apple TV will, however, screen Airplay from my iPad so I assume the WiFi part is still functioning, but somehow locked out when seeing the network. I've rebooted the Apple TV, Router (Virginmedia) and Airport Express but it makes no difference to the Apple TV, it just won't even see any WiFi networks (even if enter manually).

Is there anything special I should be doing, apart from asking Apple for my money back, or at least asking they release 5.1.2 to solve this issue? This is very frustrating as I've invested in the Apple way for simple connectivity and sharing and now the system is compromised because of the ATV. Any help would be greatly appreciated.