Streaming music is not supported on Appy Couple. While this does seem like a nice feature, we have done extensive research about this with guests and found that the majority were not in favor. Additionally, streaming music also raises issues with music royalties.
Other ways to include information about what music guests can hear at your event are the video widget and the iTunes playlist widget. These widgets let you add songs for guests to preview. You can also add a link to a YouTube video for your guests.