I'm building a python script to automate the encoding of video to xvid. I'm using xvid_encraw for the video and besweet for the audio in VBR MP3.

Then, I use Avidemux to mux the files into an AVI. The funny thing is that it does work, there's no syncing issue, but Mediainfo reports the audio as 128kbps everytime. It does say that it's VBR but always reports it as 128kbps even thought the original MP3 average bitrate is something else (117, 125, 132, etc...).

If I mux those two same files using MeGUI (Avimux), everything is fine.

Here's my command for Avidemux:

"avidemuxcli.exe" --load "video.avi" --external-mp3 "audio.avi" --audio-map --autoindex --save "output.avi"'
I also enabled all the "Automation" options in the GUI beforehand.

Again, everything plays back flawlessly but I still wonder why would Mediainfo always report the audio as 128 even if it isn't, and only when the file is muxed with Avidemux.

I guess it could be a Mediainfo bug but I tend more on an Avidemux misconfiguration or simply bug.

Can anybody shed some light on this?