It looks like Pandora (P) is taking a backdoor approach to lowering the performance royalties it pays to trade association ASCAP. The Web radio leader has bought a tiny Rapid City, SD radio station, a move that could allow it to pay the lower fees granted to broadcast station owners. However, while content acquisition costs equaled 69% of Pandora's FY13 revenue, performance royalties to ASCAP and others only made up 4.3%. Recording royalties paid to SoundExchange are a much bigger expense. Pandora sued ASCAP over its rates last November.