Okay, this site is woah. Anyways, ebmar you need Miles Sound Tool, which used to be freeware.
I've found a reddit post that explains how you'd do it. >
I meant to leave it as a link, but this update has me confused. Nevertheless, once you've done all that has been said to do in that reddit, you can then use any audio editing software like audacity to edit the audio in whatever way you'd like.