Rhythm Saves the Day (1937)

In a 100% fictional short (meaning no performer plays "self"), Buddy Page and his Band and his Band are laboring in uniforms under the guidance of an old-fashioned band leader who favors military marching music. Faced with dying a slow death if they continue the dull radio programs, Buddy calls in a group of talented black kids, the Cabin Kids, to walk the town with signs advertising a free performance by a swing band in Central Park. The Kids perform their rhythm numbers, and band vocalist Alice Dawn contributes a song.