Woodland Hills-based Music Reports, the provider of music copyright, royalty accounting, and rights administration which is owned by private equity firm ABRY Partners, reported today that it is working with social music service Rdio. Rdio is the the new social music service founded by Janus Friis and Niklas Zennstrom, the founders of Skype. According to Music Reports, it is working with Rdio to administer the mechanical licensing and royalty accounting for Rdio's new music subscription service in the United States. Financial impact of the win was not disclosed. Music Reports will help Rdio pay royalties and generate music usage reports for music publishers. Music Reports is headed by Douglas J. Brainin.