Changing volume using coordinates

Need some help here.

Id like to increase the volume of a sound loop gradually as the
mouse gets closer to a button or mc, and decrease the volume
as the mouse moves away.

Im a bit of a beginner to actionscript, Ive found one tutorial that
is basically what im going for, but it doesnt provide the fla, so
i couldnt figure it out. its here:

http://iat.ubalt.edu/courses/old/pbds668.185_Sp02/noisyRoomImproved.shtml

Can someone explain. Its for a school project. Thanks.