The v350 sometimes gets in a hung state where the screen will light up, but then fail to respond to all key presses and go back to sleep. The only way to get any response at all is to press the power button to turn the screen on. The phone cannot be powered down in this state. Holding the power button for a long time does nothing. The only apparent way to reboot the device is to pop the battery out! What are the secret key combinations to do various kinds of resets? I discovered through experimentation that holding the volume down and the power at the same time would cause the phone to vibrate until releasing the buttons. I did not let it vibrate for more than 1.5 seconds, in fear that I might lead to a destructive factory reset or something. What would have happened, had I continued?