Draw an object of size x when audio plays?

So, for a project in my programming class, we're to create a game.

My team is doing a small "blockhopper" where a block moves to the top or bottom of the screen when the player presses a button.

We would like to initiate a music track on the start of the level and have lines of size "x" be drawn when an audio clip plays for "x" amount of time. Preferably with the ability to randomly select the position at which the line is drawn (top or bottom of screen).