Hi, For the last week or so my 12.9 Pro (128GB wifi, in case that is relevant) has frequently produced a sharp burst or crack of sound shortly after unlocking the screen. It doesn't do it every time, but maybe 7-8 times out of 10. It seems to do it slightly more often when the screen auto-unlocks due to Smart Cover being opened. Has anyone else experienced this? I'm using the latest non-beta build of iOS. I'm a little concerned this is a hardware fault so I want to try and address it whilst I'm still within warranty! Cheers for any suggestions!