mp4 codec, AC3 volume

Hey guys, what's a good mp4 codec? One that can be used by Winamp/WMP.

Also, why is it when I play AVIs with AC3 audio, the volume is really low?

what's a good mp4 codec? One that can be used by Winamp/WMP.
Firstly, mp4 is actually a container format such as ogg or mkv. If you want a good MPEG4 AAC encoder, neroAacEnc is a good encoder. WMP probably needs a AAC decoder to play it.

http://www.nero.com/nerodigital/eng/Nero_Digital_Audio.html
http://forum.doom9.org/showthread.php?t=110970

Also, why is it when I play AVIs with AC3 audio, the volume is really low?

Probably because they don't compress the dynamic range of AC-3 as terrible as CD..