I explored google and StackOverflow for how to add background music to the video and many of them suggested to use

```
ffmpeg -i input.mp4 -i audio.mp3 -shortest output.mp4

```

I have been trying to achieve this but it just does not work. When I try to add map like

```
ffmpeg -i "input.mp4" -i bg.mp3 -map 0:v:0 -map 1:a:0 oo.mp4

```

The video sound is replaced by the bg.mp3

And if I try `-map 0 -map 1:a:0` or not provide map, the audio is not added at all.

How do I add the background music? I don't also get any error.