I have a 6800 that I got about 2 1/2 weeks ago... I love the phone, but I'm having a problem with it that I've actually had with previous Nokia's I've owned (both 6160 and 8260) which is the phone simply shutting off... it has happened a few times with this phone, once I was on a call and hit the end button and it turned off... any ideas on why this would happen? Help is appreciated, thanks!