radio question

[Denbear10]

Hi all, I'm a newbie with an E53 X5 01,

RADIO question, i have the small screen with the 2 knobs on it with sat/nav tv...here is the question, the radio doesn't make any noise as it was muted, but the TV and CD changer make audio noise..(Music)

Wondering the Sat/Nav gizmo in the left side panel, is a dvd player for the sat/nav, can i replace it with a DVD burner, so i can place in updated burnt dvd of where is for the bimmer..

cheers...