Hi Rachel,
What an interesting question! glad you asked it because I think I have the answer :)
Me, personally, think that audio is extremely important in shaping the narrative because it can help direct the audience in the direction of the storyline, for example if the music is soft and gentle then they are to expect something calming and happy to occur, where as if it is heavy and fast paced with a low beat indicates a more serious event to happen.
I hope this jas been useful to you and ive ehard you know someone called emily?? well she says hi.
Love Kimberley xx