Can't record

[Robert Silberstein]

I have downloaded Audacity, but cannot record. I use a Roland d-50 midi keyboard and an M-Audio interface and have Windows Vista. It works fine with Finale 2008 which I use for songwriting , so I assume things are connected properly. When I click the record button on Audacity, it goes through the motions but doesn't display the "wave" pattern, so I know it isn't recording. Playback produces no sound.
Can anyone help?
Thanks,
Bob Silberstein