So, I have searched high and low for any idea on what it might be, found a possible answer on another thread with the problem pertaining to WiFi/3G connections disappearing, but that issue is a bit different from mine. I have found nothing that could explain except for the hopes that PR1.3 will roll out soon here (US region, so, no idea when/how that will happen, but my phone came when I bought it updated to PR1.2), but aside from that, I have no idea what it could be.

I have AT&T in the US network, and the 3G works GREAT, when it wants to work. I know of several spots where my phone will still work with the 3G internet, etc., but will NOT make calls, nor receive them, nor texts, nor receive those either. The texts get stuck at 'Sending', and will eventually end up in failed over a period of time. The calls never get to the 'Calling...' animation, and always ends up with the network error sound, and the phone states in a message that there was a network problem.

Now, I am not sure if this has to do with the fact that it's an N9 in the US, but I have searched for AT&T specific issues regarding the N9 and I have found nothing. Switching the phone into flight mode while the phone is not getting service, successfully disconnects, but upon turning flight mode back on, it will never regain service.

I am not sure what to do. Anybody else have this issue? I love this phone, so I will deal with it if I have to. Thanks!