AT&T sent me a Cisco 3G Micro Cell (MC) to solve a no ring problem.
The MC caused a new problem - where the other person on the call would stop hearing my voice. I called AT&T many times over 2 yrs about this new problem & their Reps denied the problem existed.
A Google search on: MC problems returns millions of entries.
With AT&Ts knowledge, I:
1. Replaced my iPhone
2. Ran the new iPhone in factory mode
3. Replaced my SIMM card
4. Replaced my router
None fixed the problem. I spent 60+ hrs trouble shooting for AT&T.
Last week I read a Forbes article there is a known problem between MC & iPhone.
http://www.forbes.com/sites/anthony...-experiencing-problems-with-iphone-5-&-ios-6/
I called AT&T to learn a new black MC is available, which they sent me and seems to work without dropping calls.
I called Cisco today and found an engineer who said there WAS indeed a known MC firmware & iPhone problem but the black model fixes it.
http://www.cisco.com/c/en/us/solutions/service-provider/mobile-internet/att_microcell.html
Between Forbes & Cisco, AT&T was withholding the truth these past 2 yrs & knowingly distributing faulty MCs to the public.
If you are having MC and iPhone or Android problems, call AT&T and request a new Black Micro Cell immediately.