It is possible to upload audio files, we have a whole page of them. They were uploaded as MP3's, see link below: www.maurysmusic.com/acoustic_guitar_pickup__audio_clips
We also have a whole page of video clips for our Martin Guitars. They were uploaded as WMV's, see link below:
All you have to do is:
1)upload your audio file to the "file manager"
2)after it's uploaded click on view
3)highlight and copy the URL for the file
4)go into edit on the product you want to add the link to
5)highlight the words you want to use for people to click on to view it (i.e. listen here, etc)
6)click on "link to" and select http:// for your link type
7)click inside the empty box (where the link goes)
8)hold down ctrl + v in at the same time and your url will appear in the box
9)delete the http:// in the beginning of the URL because it is automatically added and if you don't remove it your link won't work.