Ok to cut a long story short i have a few hundred "video files" in avi and divx formats

Most of these will play on a media center fine (Pinnacle Showcenter 250HD)

However there are a few which the video plays fine but the audio is missing, but if i play it on a media center PC with VLC it works fine so i know its not a missing audio track.

I am assuming that is because the audio track is in some format (ac3?) rather than mp3 or wav the media center doesn't recognize it therefore cant decode it and therefore only plays the video, i have also done a firmware upgrade to see if it helps.

So assuming the above is correct maybe changing formats as its only guess work id assume simply converting the audio tracks on these non functioning videos to something the media center does understand such as mp3 would fix my problem but here lies the big question.

I need the name of a software that can recode ONLY the audio tracks of a video file, leaving the video alone as re-compressing will loose quality and be able to do this fairly easily, even in batch as i don't want to have to manually do something to 100+ video files. Any ideas?

You should give SUPER a try, it's free yet powerful video/audio encoding program:

http://www.erightsoft.com/SUPER.html

VirtualDub would do the trick:
http://www.virtualdub.org/

• Under Video, select Direct stream copy
• Under Audio, select Full processing mode
• Under Audio -> Compression, select LAME MP3 (you'll have to install LAME first, obviously). It might come with another MP3 encoder that you could use, but I can't recall offhand.

Video direct stream copy will leave the video as-is.

Yep VirtualDub works too.

8) Your both stars i'm going to go with virtual dub though as i used it some time ago for a short period its exactly what i needed thank you!