When driving at night, I appreciate the ability to dim the interior dash/screen lighting to maximize my night vision sensitivity. One option is adjusting the dashbord light intensity. Fortunately, the navigation screen automatically changes to night mode with a black background. When listening to the XM radio without the navigation map, I enjoy glancing at the screen to check the title and artist text along with the selected channel options for the favorites selection at the bottom of the screen. The bright blue screen background is fine for the daytime but much too bright and distracting at night. In the menu, adjusting the screen brightness seems to work only for the navigation screen. Turning off the screen display elimintes all the title/artist and channel information leaving only dark screen with a small time display. How do I dim or elilminate that bright blue screen backgroud for radio mode at night? As is, a definite safety hazard for my old eyes.