When I first start up the Ainol Novo 7 Paladin, I do not have a problem unlocking the screen. However, after it goes to sleep, or it when I sometimes press the power button to lock the screen and turn it back on, the screen unlock slide is unresponsive. I have tried setting it so that it never sleeps, but then the screen just stays on all the time. I have also tried completely turning off the security to unlock the screen, but once the tablet screens fades and I tried to turn it back on, the screen unlock slide is unresponsive. Is this a bug, and is there a fix?