S2X often will shut off, and then continue to vibrate lightly about once every two seconds, like clockwork. Restarts pretty quickly, but happening more frequently and is an inconvenience. This exact same effect can be duplicated on a working S2X by holding down the power button for several seconds when the phone is in standby mode. Probably related, often when I press the power button to turn the display on or off, the phone will act as if the button was pressed twice - so I press once, display turns on, then off a second or two later, or vice-verse. A friend of mine who also has the S2X has had the same issue. He thinks it was related to his using a non-samsung micro-USB charger for a week, but I'm convinced something is up with the power button on mine. Any help is much appreciated, thanks!