Delete a level in memory

Hi all, i’m developing a game where a level is created on a certain frame on the timeline. The level is described in an external .as file. So lets say at frame 5, i just did a

var level = new level();

At the end of the level, in the level code itself, I make the timeline jump to a to lets say frame 10, signifying the end of the level. The problem is, the eventlisteners and whatnot that I created in the level seem to be still existing. On frame 10, i set the level variable to null, but i can still hear the sounds triggered by my event listeners in the level class.

How do I completely remove the level from memory?