I read that the DVDs of the show had to be altered because of music licensing issues.
True. DVD release of WKRP has generic music replacing well known songs.
All over the web I can find the story about the show’s playing of Blondie’s “Heart of Glass.” It was widely credited with helping the song become a major U.S. hit, and the band’s record label Chrysalis Records presented the producers with a gold record award for the album Parallel Lines, on which the song appeared. This gold record can be seen hanging on the wall in the “bullpen” where Les, Herb, and Bailey worked in many of the episodes in the second, third, and fourth seasons.
Can’t find this on the web but I read years ago that the show wasn’t supposed to play “Heart of Glass” when they did. They were supposed to wait a couple of weeks to air the show to coincide with the song’s radio debut. It accidentally got played so it premiered on WKRP first.