Its been 2 week i took my Lumia 920... its freezing atleast once a day.. not at any particular app or screen.. its very random.. ex: once typing a msg, checking Nokia Maps, its very random, and it freezes for about 15 min and restarts on its own... any body facing this issue?? i re-flashed the entire Windows 8 again but the issue remains the same.... suggest me what to do next!!