Like the title says this thread will describe a way to change the playing song wihtout using any of the built in scripting commands.
To change the song what you have to do is write the correct values to the following offsets:
The above locations hold the two bytes that identify the song that is being played but also holds the data for the next song to be played. You can write a sappy song ID to this location, but you have to keep in mind to flip the bytes, e.g.: 0109 => 09 01
Just writing to those offset will not cause the music to change but writing to the following offset will:
Write a 1 to that offset and the game will load the new song.
This can be easily tested with the following script: