You can use BB TestAssistant to add sounds to a movie. These sounds can be anything from a simple effect that adds emphasis to an event; through to recorded speech providing an explanation for what is being shown.
There are two different ways of adding sound to a movie:
By adding a sound file at a particular point in the movie. See Adding sound files for more help.
By recording sounds using a microphone, for either the whole movie or part of it. See Recording sound tracks for more help.