Every time I close my laptop lid, Ubuntu 13.04 will lock up. I have it set in the Power settings to do nothing for when I close the lid on both battery power and when plugged in, yet when I do close the lid, the system seems to lock up. Note, the mouse will move as normal, and it looks like nothing is wrong. But when I try to click or press any buttons, the system is unresponsive. I have to power cycle the laptop and re-boot in order to continue using it. Any help would be appreciated!