I have had the same problem since the JB update as well since the first week of Nov. I had a replacement M sent to me - same problem. I have called VZW everyday for the last week to ask to exchange to the iPhone 5 at contract pricing and they told me to pound sand. My options were to add a line to get the iPhone 5 at contract pricing, or purchase an iPhone 5 at full retail, or find an iPhone 5 outside of VZW.
I am a die hard Blackberry fan, and I reluctantly switched to Droid for the purposes of getting more app functionality. So far, I am furious and unsatisfied. Since VZW approach to solving my problem is for me to spend more money, I sent a complaint to the BBB and I sent correspondence to VZW corporate customer relations.
The issues you described would be very frustrating! That's not a known issue that I've encountered after the update. I'm sure we can work together and get this addressed!
Was the device exposed to any physical or liquid damage? After the factory reset did any 3rd party applications redownload on the device? Please power the device in safe mode and retest. Here's how: http://support.verizonwireless.com/clc/devices/knowledge_base.html?id=63868&sayt=safe mode *
Please let me know if the issue persists.
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