Okay, I managed to download the video I wanted and even extracted the audio file from it via MPEG Streamclip. Now what I want to do is edit the audio portion so that the only thing I have left is a song that is somewhere in the audio clip. I don't know how exactly to do that. I tried using GarageBand but couldn't open the clip for some reason. There's probably over 7.5 minutes of audio but the song starts somewhere around 1:55 and ends around 4:24. I don't know how to do this. Can anyone help me?