Emily (a.k.a. The Pink Pearl) - S4-E13
Audio problem: During the scene where John Sears and some of the keg brothers are telling Steve that one of his hazing duties is to steal Professor Randall's signed baseball, pay attention to the camera shot behind John Sears when he is talking to Steve - his lips do not match what he is saying.
Answer: There was no explanation. Usually, when a show doesn't know if it's going to be picked up or not, they will use stock footage until they can spend the money on a real location.
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