After 5 years away from Mercedes, I have returned with a 2008 W204 C320 CDI Sport :bannana: After searching the forums and reading the manual etc I think I have the Audio 50 Navigation system (Small colour screen, not the flip out larger screen). It has Navigation, Live traffic Information, Harmon Kardon Sound system, Bluetooth, Aux in glove box. So a couple of questions: 1) Is it possible to add USB or SD card slot? 2) Where is the Navigation DVD played from? When I press eject on the cd drive nothing comes out? Is the navigation DVD played from somewhere else (boot?) I have the original Navigation DVD case in the glove box. 3) Is it possible to play audio via bluetooth on this model? Thanks in advanced for any info.