Monster Sound Show
From Disney's Hollywood Studios Wiki
 Show Synopsis
Guests started with the pre-show film that was shown in the outdoor queue area, which starred David Letterman. In the film, Letterman provided a funny introduction to the attraction and gave guests a good idea of what was to follow in the actual attraction. It featured Letterman on his talk show set doing a segment with a sound artist. A great quote from Letterman to park guests in the film was, "If you break anything, security guards in mouse suits will beat you senseless."
Once inside the 270-seat theatre four members of the audience were volunteered to add the sound effects for a short comedy film in which a Master of a hotel, played by Martin Short, attempted to kill an insurance salesman, played by Chevy Chase. Professional sound effects used included Thunder, creaking doors, breaking glass, rain, etc. The short film was shown three times in all - the first showing was the original, the second, where the audience members attempt to add the sound effects, and the third showing was the result of the additions. Overall the whole show lasted for 15 minutes, and featured loads of the sound-effects gadgets created by sound master Jimmy Macdonald who worked for 45 years with he Walt Disney Studios in California.
After the main performance, other guests could try their hand at adding sound effects to classic movies in the Soundworks postshow area, which is the only part of this attraction that is still there today.
What made the attraction fun were the volunteers who attempted to place the sound effects into the film. The premise of the attraction was to show the importance of sound in a film and also it's not as easy as one might think. Often the film would result with a knock at the door being heard after the door is opened, with the sound of glass breaking when it should be of paper rustling. There was actually a hidden Mickey in the film when Chevy walks up the stairs and knocks on the door of the house. If you looked carefully to the lower left of the door there is a flower pot. When the lightning strikes you could clearly see the pot is shaped like Mickey.
This show was preceded by the ABC Sound Studio show, which was the same in essences but had a different video.