Audio problem: Just about every time someone starts or stops a cassette tape, we can see that they're either faking it or pressing the wrong button. In one shot, the 'Pause' button is down both before and after the actor presses 'Play,' which would of course mean that the tape shouldn't play at all.
Audio problem: Around half an hour into the film, some kids are listening to a tape of the radio show and a teacher takes the tape out because he doesn't like the content. As he takes the tape out, the audio ends right after the tape door opens, when it should have ended a little sooner, if it was actually coming from the tape player. (00:32:35)