Problems converting videos [audio related]

I'm using Total Video Converter to convert videos
I never use it before, and today when trying to convert an avi file I get this:
"Error while opening codec for output stream #0,1"
I search on the internet and I realize it's not related with the converting program, I think it's about codecs. I only have ffdshow installed (one of the latest versions) and I can view any type of files without problems.
I realize that changing the audio of the video from mp3 to aac get rids of the error but the video has no sound.

I listen to any ideas.

 

I would download K-lite codec pack. It's probably more codecs than you will ever need but once installed you shouldn't have any codec problems in the future.

http://www.majorgeeks.com/K-Lite_Codec_Pack_Full_d4844.html