Myself and Peter felt this clip was made up of 3 stages
Sound of the distant train is warped and distorted due to the distance and speeds.
The travelling train offers a good sense of time and space as well as an ominous tone.
The music is symbolic of the action within the scene and the added textures onto it represent the danger the train is due to encounter, it also mirrors the repetative nature of the train. We felt it sounded similar to a siren like warning tone.
Sound tends to disappear when the focus of the action alters and is pinpointed to a specific area... (such as Jesse listening to the tracks)
The screeching of the trains wheels are reminiscent of screaming, this could represent the helplessness and vunerability of the passengers.
The dialogue makes the relationships feel tense and untrusting.
The sonic style reminds us of stalking and a sinister character creeping up on unknowing prey.