I want to add some music files (.mp3/.ogg) to the actual "gameambientevent_bank00.fsb", a file related to League of Legends.
The files inside of this fsb are .celt-files without a header.
Now I want to add a new soundfile to it (rebuild the fsb?).
The celt-file format is this:

Can you tell me if it's possible to add new music to it and get it to work?
I want to do this because I was able to readd a OLD Map (Old Twisted Treeline) and I want to use the original soundtrack for it.
I uploaded the fsb
http://ul.to/4mvs15q7