Mci Control Use

Hi, can someone please give me a hint on how to use the Mci control. I want to use it to play mpeg-files. I´ve created a dialog and placed the control there, and then made a member variable of the MFC wrapped class Cmci. I´ve tried to use the onbuttonplay but then I got stuck cause I don´t know what to put there. I guess I need to setdevicetype to DigitalVideo, which I have tried and I also tried the SetFileName. But How do I actually get it to play the selected file? Please help, I´m stuck.

Frederik.