Replay Converter is an audio/video converter. It allows to extract audio tracks (like MP3, AAC) from video files.

How to extract AAC audio track from FLV files (with AAC audio) using Replay Converter:

1. Open Replay Converter
2. Hit the "Add files" button on the right.
3. Select your FLV file(s) and hit the "Open" button.
4. In the main window of Replay Converter right-click on your FLV file (or select multiple files and then right click on one of them).
5. Select "Extract".
6. Hit the "OK" button (Repeat this step for every FLV file you want to extract AAC audio tracks from).
7. Hit the "GO" button in the main window to start the extraction process.

Note that Replay Converter will extract AAC audio tracks from FLV files using AAC audio, MP3 audio tracks from FLV files using MP3 audio, ...