??? I have noticed that occasionally the HUD does not display the XM station information when the XM channel is changed, and if that part is malfunctioning, and I have turn by turn activated on the navigation system, that too will not display the upcoming turns on the HUD as it is supposed to. I also noticed it occurring (intermittently) on several other Acadia's that I recently test drove. My Acadia has only 600 miles on it in one week of driving and it has happened about 2 or 3 times. I have contacted my dealer who told me there is a Technical Service Bulletin (TSB) from GM that indicates there is a known issue with the Delphi Navi Head unit intermittently not communicating with the HUD. There is no know resolution for it at this time but they are "working" on it. Anyone else with Navi and HUD noticed this on your Acadia? Any fix that you may be aware of??