Multimedia Dock


I bought a Multimedia Dock with my Motorola Droid, and when I put my phone into the dock instead of the multimedia screen coming up when its plugged in the Car Home screen comes up. I was wondering why this is? I downloaded a Dock Runner Application but I dont want to have to continue to turn on the application just to get the correct screen to pop up? Anyone have any ideas on why it does it what I can do to fix the problem?