Got a new airport extreme and set it up and with many different devices, the apple iPad and iPhone 4 both don't remember and join the network. If I leave the house and come back I have to go into settings and select the network and enter the password. Same when rebooting the iPad. But apple tv, TiVo, ps3 and Mac all stay connected or remember the network and password. What could I be missing on the phone and iPad. (and now ipad2).