Congress should change music-royalty rules so Pandora Media no longer pays half its revenue to artists and recording labels, Chief Strategy Officer Tim Westergren said.

Pandora’s royalty rates are higher than for satellite radio company Sirius XM Radio, which paid about 7.5 percent of revenue last year, Westergren said in an interview in Washington. Traditional broadcasters don’t pay such fees for over-the-air music play.

“It’s a bizarre lack of parity that’s grown up over time,” Westergren said.

Westergren, Pandora’s founder, in testimony prepared for delivery at a congressional hearing today, said it’s “time for Congress to level the playing field.”

Pandora offers customized playlists to 125 million registered users and generates most revenue through advertising, according to a regulatory filing.

Lawmakers should set a standard for music delivered over the Internet, Westergren said.