sueh

OK I have a stupid problem but trying to figure it out without going back to where I bought the car!
Have a 2000 ml 320 The ad said "single CD" but it wasn't in dash. When I asked about it, they said it was in back. We looked, wiring was there but no CD player. Took it back. They agreed their mistake and put in an MB 6 disc CD changer.
Now I can only play one cd....even though the readout says "CD Changer" and shows in icon with 6 stacked CDs, I can't figure out how (or IF)to change it from CD #1 to any others that are stacked. IT just keeps playing the #1 CD. (I'm getting pretty sick of that CD by now!)
AM I totally missing something here or what?
Any help is appreciated!!


This is my first MB....it's old but it only has 70K miles and is pristine condition. Loving it so far.