I'm sitting in my kitchen today with 5 bars of signal. Three rimes today, the signal totally drops and the phone says "no signal" - just dropped it. Then I reboot the phone, and it says "no sim". I reboot again, and same message. reboot again, and it locks in 5 bars of signal, no problem. Today is the first time this has happened - it's been perfect before now. Anyone else having this issue at all? Sounds like it could be hardware or software related.