Those with freezing issues: Do you have creeping current on the Macbook's chassis (stroke it with two fingers, do you feel a tickling)?
When you connect an external display, powered USB hub or anything else that comes with its own power-supply, does touching the Macbook 's chassis around the USB/Displayport with the external connector cause a short sparkle/flash (turn off the light in the room to make it more visible)?
When you connect an external display, powered USB hub or anything else that comes with its own power-supply, does touching the Macbook 's chassis around the USB/Displayport with the external connector cause a short sparkle/flash (turn off the light in the room to make it more visible)?