There is a lot of reviews and forums on 920, I checked em out before picking the 920, never ran into your issues on any.
Sounds like a serious call to your wireless supplier is in order. Good luck.
It’s all over the internet. Just use google.
Basically, if you want advanced features, car/headset handoffs, turn by turn navigation seamlessly integrated with calls coming in, etc you are SUNK with WP8.
If you want to JUST use it occasionally as a phone, it’s OK. But WHY BUY A SMARTPHONE?
Face it, It SUCKS as a smartphone. I know what I am talking about - I have had EVERY smartphone since the ERICSON p800 (that was BEFORE the Blackberry OR the iPHONE). I am a power user of phones, been using bluetooth when there was only 1 phone that supported it.
As a VERY experienced user, I can tell you WP8 is the buggiest smartphone I have ever used. PERIOD.