Removing hiss from HD video recording

[canonmj]

I use Creative Vado HD 3rd generation to record acoustic music. The file is saved as MP4 through Quicktime Player Pro. How can I reduce background hiss from the audio portion?

Thanks for any suggestions.

[steve]

You may not be able to, but let's look at the options:
1) Are you able to import the files into Audacity and have them play correctly?
2) Are you only concerned with audio or are you wanting to clean up the sound on video files?
3) Have you read this: http://manual.audacityteam.org/man/Noise_Removal