Audio trigger by key press - problems

Hello I want to play sounds on certain key presses so far what I have makes an awfully distorted sound - tried aiff, wav, ogg. What am I doing wrong/missing?

var audio01 : AudioClip;
function Update () {   
    if (Input.GetKey  ("1"))
   {
      audio.PlayOneShot(audio01);

   }
}

thanks in advance Daniel

Try changing it to:

if (Input.GetKeyDown ("1"))

Otherwise, it will start playing the audio every frame that you have the key pressed.