Alf Clausen, who has been the composer for The Simpson's since 1990, has been fired, according to Variety:

Clausen told Variety that he received a call from “Simpsons” producer Richard Sakai that the company was seeking “a different kind of music” and that he would no longer be scoring the longtime Fox hit.

While Danny Elfman wrote The Simpsons theme song, Clausen has been responsible for all the incidental music on the show since the "Treehouse of Horror" episode in Season 2, and his work includes the closing credits music, the "Itchy & Scratchy" theme, and many of the show's many songs, like "We Put The Spring In Springfield," "Who Needs the Kwik-E-Mart?," "We Do (The Stonecutters' Song)," "See My Vest," the songs from the "Stop This Planet of the Apes I Want to Get Off!" musical, and more. He's been nominated for 27 Emmys and has won two for his work on The Simpsons. Simpsons creator Matt Groening has called Clausen, "our secret weapon."

While FOX declined a comment to Variety, some have speculated his firing could be a cost-cutting mechanism -- Clausen used a 35-piece orchestra to record each episode's music. Stay tuned.