I had this problem and found that the rotation lock switch when in the on position also works to change the orintation when you press down. The slide across function only locks the switch from being operated. I belive a lot of people are resetting when all they have done is inadvertantly pressed the switch.
Own a Predator Laptop? Then I bet you have learned a thing or two from beststevie. He has been helping out in this forum for quite a while and it's about time we recognized him for it. Thanks beststevie!