Can't run spotify through LMS

Ok I am pretty sure this is covered somewhere so if someone can direct me that would be nice and then I can shut up and stop wasting everyones time.

I am running LMS on an IMAC running mountain lion. I tried to play spotify using the app from LMS but it does something strange. It doesn't play at all but I can see the computer playing the first 5 seconds of each song in the playlist and then going to the next one. Still no sound comes out of teh speakers.

Any help is appreciated

Jerry