Correct way to normalize two audios before using filter_complex amix
One way to make the volume levels consistent is:
ffmpeg -i in.mp3 -i out.mp3 -filter_complex &quot;[1:a]asplit=2[sc][mix];[0:a][sc]sidechaincompress[compr];[compr][mix]amerge&quot; -c:a libmp3lame res.mp3

But this may not be the best way. Please let me know if there are better ways, and what are the pros and cons of the above method. thanks.