I wonder if anyone can help me?

I've just bought an 08 2.7 TDI Le Mans Avant with mmi basic plus and a single CD player in the glove box.
Can this system play mp3 CD's or is it only the CD multi changer that will play mp3 CD's?
The mmi shows CD ROM when I put an mp3 CD in but nothing else!

I know this has been asked on this site before but I have not been able to find the answer.

Everything else about the car is excellent, should have bought one years ago!!