iPad Air and an accelerometer problem

  Using the tablet iPad Air during this day I noticed that in iOS there is a small problem regarding the accelerometer and the screen rotation system. More precisely, several times the tablet refuses to change the orientation of the screen from landscape to portrait mode, all out of the blue, after a simple unlocking. Of course, a lock/unlock does not solve the problem in any way and the only way to return things to normal involves reopening the tablet using the Lock button.

  Unfortunately, this is not the first time I encountered the problem, the tablet iPad 3 generating the same blockage several times, but not as often as iPad Air. I don't know what exactly is wrong Apple Lossless Audio CODEC (ALAC), in its iOS, but I notice that it is not something limited only to certain models of the iPad, and even the iPad Air is not free from problems. Have you encountered a similar blockage while using the tablet? iPad Air?