iPhone5 with iOS6.1 airplay disappears after reboot

I'm trying to connect to AppleTV3 with my iPhone5 with iOS6.1, they are on the same network with Comcast modem and Dlink DIR-655 router. If I reboot my phone and then go to pictures the airplay icon is there and I can see the pictures with the ATV3 but, after the phone goes into standby and I swipe to turn back on, if I go back to pictures the icon is now gone but if I reboot the phone again it comes back util the phone goes into standby again. Why would this be happening???