How to convert .mp4 videos to .fla format.
Converting MPEG-4 Videos directly to Free Lossless Audio Files (.mp4 to .fla conversion) should be possible and straightforward. It relates to users attempting to extract the audio track (FLA) from an MP4 video.
You can use one of several available multimedia editing programs or (online) conversion tools, such as Helium Music Manager or MediaMonkey, which allow users to import MP4 videos and re-save them in FLA format.
A set of audio and ripping utilities for Windows