I bought a MacBook a few months back, and have been using it only for school and business. This is my first Mac, and it has been pretty easy to get used to and I really like it. However, when I transferred several of my video files from my old PC, the .avi files don't have sound. I downloaded both xVid and DivX codecs assuming that one of these would be the solution, but still no sound. I have limited experience with QuickTime, but all the software is up to date and the newest version of QT, DivX, and xVid.

Any help would be great. If anyone has any tips for newbies to Macs that would be great too. Thanks!

You need to install this codex

http://mac-tech-switching.blogspot.com/2006/09/avi-no-sound-problem-solved-today.html

Thanks. That specific link didn't work for me, but after reading about the a52 codec, I did some google searching and ended up finding a program called Perian. This is available at www.perian.org, and is a compiled group of DivX codec and several others for use with quick time. I appreciate the help, and I hope if anyone comes up with the same problem that is a helpful solution.

I was just about to recommend that.

It's good and works for most of my videos.
I think Perian installs the a52 codec for you, but I could be wrong.
I also have the Divx codec installed, but not the Xvid codec because both Perian and Divx can handle Xvid.

Also download VLC Media Player (www.videolan.org)
It will play almost everything you throw at it.
It's good to have around when Quicktime doesn't play nice with your Videos.

Peace.