Anyone know what that Traffic button does on the bottom right? When I press it says something about setting it to a XM Traffic channel. I have XM Radio enabled. I also have the NavTraffic Service. What is the point of this button and what does it do?

Its like preset button for the XM traffic channel local to your area. Usually in the 200s I think. Find your local traffic channel number and then set it

I wish this button could be programmed to user preference. If you don't buy the XM and traffic, this button is a waste of good realestate.

^^ Yeah, that would make a nice MUTE button IMHO.

Holding down the Source button works but it has a couple seconds delay.