Good luck. I recommend using the audio-editor, with which one is most comfortable. If one does not have an audio-editor, then Audacity is a good one, and it's free. There are several tutorial articles on using Audacity at Muvipix.com. I use Adobe Audition, because I know it, like it, and it works beautifully for me. However, it is not free, though is included with several Adobe suites, and has recently been ported for the Mac.