Adjusting the sound file: 1. Download Audacity if you don't have it already. 2. Launch Audacity and Import the Audio File 3. Highlight the track and click the effect drop down 4. Find the equalization filter in the drop down 5. You should see a graph with a blue bar to adjust the decibels at different frequencies. The human voice is around 100-5000 HZ. Adjust the bar to cut off sound lower than 100 and higher than 5000 db. Click okay and it will do it's thing.

This will eliminate any unwanted background noise. Audacity has some presets for voices apparently which might be better, but just cutting it at 100 and 5000 worked fine for me. Here is a youtube tutorial on how to adjust it too.