I am having the same issue on a AT&T Branded Moto-X. Whenever I end a call my cellular signal drops to 0 bars and takes 15-20 seconds before it comes back. Very annoying, I too would like to know if this is an AT&T issue or the phones....
Seems to be only impacting HTC devices from the thread I am following over at Google support. Makes me wonder what HTC did differently...
Posted via Android Central App
I am having the same issue. Did a factory reset and Friday and thought the issue was resolved. However on sunday I noticed that the problem has come back.
Posted via Android Central App
Here is video shot on my nexus 7 showing my very tired htc incredible 2 running jellybean. It needs to reboot several times a day to get its rest, would love to win an htc one! Thanks AC!