MP2
        MPEG1 Layer 2 audio, later replaced by MP3, is used on video DVDs.
        
            Options
            
                - 
                    Bitrate (number)
 Set a specific bitrate in kbps to control file size. Default is 192.
 bitrate=256
 
- 
                    Mode
 Set the encoding mode.
 
                        - auto: select automatically
- stereo: stereo
- joint: joint stereo (default)
- dual: dual channel
- mono: mono
 mode=stereo