There's a reason Widespread Panic can sell out arenas but can't sell enough albums to earn a gold record. Live music is all about playing, while recorded music is all about songs. And while these six Georgia musicians can play superbly, they can't seem to write a memorable song. Their melodies are derivative and repetitive, and their lyrics strain for a cleverness and meaning they never quite grasp. The group tries to beat its studio jinx on its new album, "'Til the Medicine Takes," but the band attacks the wrong problem.

Instead of overhauling its songwriting, the group changes how it plays the music. There was nothing wrong with how Widespread Panic played, but the band nonetheless brings in Big Ass Truck's Colin Butler to add hip-hop scratches to "Dyin' Man," church diva Dottie Peoples to add gospel wailing to "All Time Low," alt-rock diva Anne Richmond Boston to add ethereal harmonies on five other songs, longtime producer John Keane to add mountain banjo to "The Waker," and the Dirty Dozen Brass Band to add New Orleans horns to "Christmas Katie."

These contributions are integrated tastefully and they add spice to John Bell's gruff, soulful vocals, Michael Houser's psychedelic guitar solos and the rhythm section's elastic sense of groove. But all the guests in the world can't help songs of no inherent interest.

Appearing Saturday at the Merriweather Post Pavilion with the Dirty Dozen Brass Band. To hear a free Sound Bite from Widespread Panic, call Post-Haste at 202/334-9000 and press 8110. (Prince William residents, call 690-4110.)