Trivia: One of the parents at the school board meeting is Lin Shaye. While she had been in many movies at that point with mostly smaller parts, she would go on to be well known in two movies directed by the Farrelly brothers in the mid-1990s, Dumb and Dumber and Kingpin.
Trivia: Contrary to what it appears, the actor at the post office is not David Schwimmer despite the close resemblance. Schwimmer was active at this time, but the actor is not him.






Answer: The first time I watched the movie, I kept thinking that Mark's parents were going to hear him and catch "Harry" in the act. When the girl was with Mark, Mark's parents pounded on the outside door; when Mark opened the door, his parents said they thought they heard him talking to someone. So, from outside the garage door, someone might be able to hear muffled voices but not the actual words. Why his parents cannot hear him in the basement when they are indoors lies in the props/scenery plus some inference. The numerous objects in the room (tapes, CDs, albums, guitar, drums, bongo drums, recording instruments, amps, etc.) indicate that Mark is into music - loud music - and electronics. He apparently was given garage/utility storage space to turn into essentially a studio for himself and a place to play his drums and music without disturbing his parents. The space has been sound-proofed - thick concrete walls, insulation, and cloth wall hangings to deaden the sound.
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