mkv to mp3

[gavo]

i'm trying to batch convert a mkv with aac into a mkv with mp3. I use riverpast audio converter with lame plugin and can mass encode all the aac into mp3 from there resync with mkvmerge. Are their any better ways? I tried using avidemux but it takes up to 45 min to reencode the mp3 makes no sense. Anyone now of a batch way of just grabing the mkv video file and then converting the audio from aac to mp3?

[gavo]

help

[Baldrick]

maybe ffmpeg

ffmpeg -i video.mkv -acodec mp3 -ab 128 -vcodec copy -o video.mkv

and then make a batch .bat file for it.

for %%a in ("*.mkv") do ffmpeg -i %%a -acodec mp3 -ab 128 -vcodec copy -o %%a-new.mkv

and run it in the same folder as ffmpeg and the mkvs