[twr]

Hi cyclone53, i think your right you need a external DVD player for your 2006 truck. With my GMX322 its not gps tracking if i am watching a dvd on the front screen with the lock pick turned ON. If i am just watching the rear screen with the lock pick truned OFF as it comes from hummer then the gps is tracking. Below is from lock pick. I am not 100% sure in your truck but its likely the same. So you would have to turn OFF the front dvd screen to go back to gps tracking. Hope this helps



**During the time that you are actively viewing a factory DVD or factory AUX video while in
motion, OR while you are inputting an address or taking advantage of the other radio unblocking
technology, active map tracking is not occurring (if you switch to the map view immediately from
an unblocked function, the map will not be moving or pinpointing your exact location). Press the
MUTE button two (2) times as mentioned above to immediately restore factory operation and
begin map tracking again. It may take several seconds for the map to recalculate your current
position.
**Use of the factory camera, aftermarket cameras or either of the 2 Video/Audio inputs available
on the GMX-322 while in motion does not affect active map tracking while on.