Hi, I bought my phone a few months ago and since a few weeks it's giving me problems. First, my back button stopped working (in fact I'm using SmartTouch now), then the phone started randomly shutting down when in standby mode. No logo, no nothing. Just sometimes when I press the power button to turn on the screen, the phone doesn't wake up. Then I long press the power button, meizu logo appears and the phone normally boots up again. Why is this happening and what can I do to solve the problem? I tried upgrading to flyme 6 beta but it didn't solve anything.