I have a MacPro 3.0Ghz first generation using OS X 10.5.8 with Quicktime 7.6.6 (1674) and iTunes 9. I have saved several video files with “mpg” file ext. format. The play perfectly with VLP player but I have no sound in either Quicktime or iTunes. Quicktime is my default player. What do I need to do to have audio in Quicktime and iTunes.