As radio executives gather in Philadelphia this week for the National Association of Broadcasters' annual Radio Show, attendees will likely get an earful about legislation moving through Congress that would impose new fees on AM and FM stations. The NAB has waged war against a pair of House and Senate bills, claiming they would impose an unfair burden on an already cash-strapped industry. But music stakeholders argue the bills would bring AM and FM in line with Internet, cable and satellite radio services, which already pay performers.

An NAB spokesman said Tuesday that support for "free and local radio" continues to grow despite the music industry-led effort. The group noted that 251 House members and 25 senators have signed onto resolutions opposing what they believe is a tax on local radio. Sen. Mary Landrieu, D-La., and Sen. John Thune, R-S.D., along with Reps. Dennis Cardoza, D-Calif.; John Boccieri, D-Ohio; Brian Baird, D-Wash.; Joe Sestak, D-Pa., and Dan Lungren, R-Calif., were the most recent to back the resolutions.

Meanwhile, proponents of the legislation are turning up the heat on one radio giant. The MusicFirst Coalition said Wednesday that two Washington, D.C. area Clear Channel stations -- country station WMZQ and WIHT, "Hot 99.5," -- failed to comply with public disclosure rules for advertisements opposing the Performance Rights Act. MusicFirst argued the stations played NAB spots but an inspection of their public filings found no record of the broadcasts and nothing about the stations' opposition to the legislation.

"Clear Channel's actions are further evidence of how corporate radio groups and stations are violating their public interest obligations," MusicFirst Executive Director Jennifer Bendall said, noting the activities are political in nature and are covered by the Bipartisan Campaign Reform Act and FCC regulations. Clear Channel and other station owners have previously refused to air ads produced by MusicFirst. The latest complaint was included in reply comments to the FCC, which is investigating the situation.