We've constructed an app that mixes 8 tracks of audio in realtime using a console built in flash. This works really well, but we're having trouble exporting the resulting audio to an mp3 (or any audio type) file.
I realize that the solution might come using code in PHP, or another language. We're not afraid of going into that all, if someone has any idea of how to pull this off.
As usual we need to solve this for a client as soon as possible.