Help! Episode with Bud singing in Elevator...?

I have a very vivid childhood memory of an episode of this series where Bud is in the elevator listening to his headphones, and someone/something (ghost?) gets on and asks to be taken to the 13th floor. Bud, still listening to his headphones, sings something along the lines of 'there is no 13th floor', at which point the person/ghost gets mad, and demands to be taken to the 13th floor. Bud, realizing how mad the person/ghost is, sings something along the lines of '13th Flooooor, 13th floor, bam bam!' (maybe he plays air guitar or something?).

This scene has been stuck in my head for almost 20 years. Someone help me find it!

Thanks.