automate setting sound volume in mp4

[jumi99]

Hi

I'm trying to automate editing the sound volume in mp4 video clip.
Every time I want to edit the sound volume I need to do the following steps:
- open the mp4 video clip
- set the audio output from "copy" to "AAC (lav)"
- set bitrate from 128 to 64
- set gain mode to manual
- set gain value to desired value
- save mp4 file with new sound volume

I would like to write a script that just takes the gain value as an argument and generates the mp4 file with new sound volume.
Please tell me how can I do that.

I'm using avidemux 2.6.4.

Great thanks in advance