This applies to the Launch Control
Sometimes the pads on Launch Control will start the Vegas mode light show sequence after the computer has been turned off. This happens due to the USB port still providing power. It can be annoying to have to unplug the Launch Control every time.
The solution to this is to hold the up and down arrows on Launch Control whilst pressing the right arrow.
The XL can also do this, it should also be noted that once the Launch Control connects to a computer and then connection to the computer is lost the unit goes to sleep where all LEDs are off.