I am currently using the Lumia 920 on o2 Germany and for some reason the phone just randomly stops responding to the network, calls/SMS and data connectivity just disappears. Sometimes reboot solves it, some times it takes a while 2-3 hours. During this time people are able to call me, I can take the call but cant hear nor speak.
Before using the Lumia i was using a galaxy S and i never had problems on that phone, so i doubt if its the network that is causing this problem. If possible could any other o2 germany user check if they have this problem ?