I've just purchased a new i5 128gb, I seem to have an issue with lock screen lag. I have the keyboard on and when I use it as a traditional tablet in portrait mode, the lock screen sometimes displays and doesn't get the clock on for me to swipe up. I have to change orientation and touch the power button off and on to get the lock screen back up to be able to be unlocked. I'm also getting a 5 second lag from pressing the off button and the screen turning off. Is this normal?