Marty is a DJ for KBBL. He and his partner Bill often announce the contests for KBBL radio. They also interview people, such as Spinal Tap, on their radio show. They are inducted into Springfield Wall of Fame, too.
They are responsible for giving Bart his elephant, Stampy, although they were surprised when Bart wanted Stampy, because they thought he would choose the other prize, $10,000. In another instance, they gave away two tickets to the Springfield vs. Shelbyville football game. Marty also at times plays the wrong music by accident, such as playing Monster Mash on Valentine's Day and President's Day (two holidays that didn't even fit the song).
When Mr. Burns acquired all media outlets in Springfield, including KBBL, they got fired.