I am using Macintosh with 10.6.1 OS from the past one month. Whenever I am trying to use USB headset or USB audio input device I am getting robotic static sound after usage of around of 10 to 20 minutes. I have tried everything which I can do to solve the problem of mine. I tried with various headsets and various USB port but all of my efforts were fruitless. Can anyone tell me how to overcome from this situation? Any suggestion will be highly appreciated. Thanks a lot in advance.