Why does my ipod make a strange buzzing noise if plugged into computer speakers?

That superfluous auditory interference is due to the sub-audible change in frequency associated with the iPod's proprietary speaker system. No fix exists.

first check if the balance is not adjusted correctly bydouble clicking the speaker icon in sys tray and checking the balance setting try reinstalling the sound drivers on your computer. Control panel> sounds and audio devices>hardware>in devices window, find your audio device, double click on it>in properties, select update driver, and follow thru.