I bought MacBook Air 3 days ago and I noticed I got a page that said "not connected to the internet" and the Wifi dropped off. I had to manually reconnect to the wifi connection, Okay fine strange but I guess it happens. So I decide I wanted the 16GB model and I exchanged it and the same symptoms happened again. This time I checked my iPhone and other devices and they were connected to the wifi. Is there anything I should check? Your thoughts?