Factory DVD Nav - Mp3 Support missing?

[H3PAC]

Speaking of the OEM nav unit, here's an odd thing....When I took delivery my nav DVD was missing from the box, but when I tried to eject it from the nav unit, nothing came out. The nav feature works just fine - no problems. And I can play CD's while navigating (was told that is not possible). When I start the vehicle with the nav on, the unit boots with the H3 logo, then the screen reads, "Checking DVD" for a few moments. I can hear a whirring noise coming from the unit, as if it's reading a disc, and everything everything works fine.

So what the heck? Did it swallow my DVD and still accepts CD's? If not, is the unit working from an internal HD? Why can I navigate without the DVD? The manual says not possible. Why can I listen to CD's while navigating when this is not supposed to be possible? I've done as much searching as I can on the web, but no luck. Who is the best person to ask about this? The folks at the dealership have no clue about the nav units.

Were any recent changes made to this unit that I'm not aware of? I noticed that other units I've seen have the eject button on the right, just above the screen. Mine is on the left. It's identical in every other way. I should mention that the dealer installed the unit prior to delivery, since the factory had installed the 6-CD unit that comes with the luxury package.Feels like The Twilight Zone.