Hello, I wanted to convert a avi file to mp4 file. I installed the MPEG Streamclip. However, the MPEG Streamclip plays the avi file but I can't hear anything (no volume). I have tried everything I can do on my computer. Is there are a problem with the MPEG Streamclip or something I am overlooking? The avi file works fine if I use itunes or Quicktime but there is no volume if I use MPEG Streamclip. Please help! Thank you.