Increase or Decrease the Pitch of the audio file using C#

[lemmedownload]

My want to do the followings:-- To increase and decrease the \[code\]Pitch\[/code\] of the audio file( .m4a, mp4, etc).- I am presently using \[code\]Visual Studio 2008\[/code\], with \[code\].Net framework 3.5\[/code\]- I have tried out the following link, but no success yethttp://msdn.microsoft.com/en-us/library/dd940201.aspxHere in the above link, even after importing the Microsoft.Xna.Framework.Audio, its not recognizing the \[code\]SoundEffectInstance\[/code\] and \[code\]SoundEffect\[/code\] class.So is there any work around this problem.....................