No Airplay Icon on any Apple device (while connected to wifi)

I checked that my apple tv and all my other apple devices (Macbook Pro, iPhone 4, iPad 2) are all connected to the same wifi network but i cant seem to find the Airplay Button any where not on itunes on the Mac or the mirroring button on the macbook or either the ipad 2. But when i connected to the ethernet every thing seems fine, all of the Airplay buttons appear.

But why won't any of these buttons appear while on wifi ?

For more info:

Macbook version is 10.8.3

iPad is IOS 5.1.1

iPhone 4 is IOS 6.1

Apple tv is IOS 6.1.3