Conversion of m3u8 files to mp4 file format

You actually cannot convert .m3u8 files to .mp4 audio simply because the first file is a just a playlist and does not contain any audio data, so no m3u8 to mp4 conversion is possible and no m3u8 to mp4 converter exists. At best, you can open the .m3u8 file in a text editor and check the file path to the actual audio files, but that will only be useful if you for example open that file on old computer. Checking it out on downloaded playlists is pointless.

Open M3U8 file    Open MP4 file