Talk show host Morton Downey Jr. is being sued by two songwriters who say they wrote the theme song for his syndicated show and have never received any money for it. The songwriters, John Beland and Floyd Guilbeau, both of Hendersonville, Tenn., said Downey claimed co-authorship and diverted the royalties. The lawsuit, filed in U.S. District Court in Chicago, said Beland and Guilbeau wrote the words and music "to an original musical work entitled the `Morton Downey Jr. Theme.' " The musicians, members of the Burrito Brothers, a '50s and '60s revival band, are seeking an unspecified amount in damages and royalties. Downey will not comment on the lawsuit, said his assistant, David Lloyd.