JavaScript: Sound & Points deduct On click Help!

Can anyone help me on this script that I am working on? I'm trying to be able to deduct points from "currentmagic" variable every time I click the left mouse button as well as play a sound when I click it. There are no errors and it doesn't work any help will be appreciated. Thanks!

 var currentmagic : int = 100;
 var maxmagic : int = 100;
 var display_1 : GUIText; 
 var sound_1 : AudioClip;
 var sound_2 : AudioClip;
 
 function update () {
 
 if (Input.GetMouseButton(0)); {
 
 soundaudio();
 currentmagic -= 5;
 
 }
 
 if (maxmagic < 5); {
 
 audio.PlayOneShot (sound_2);
 
 }
 
 
 }
 
 function soundaudio() {
 
 audio.PlayOneShot (sound_1);
 
 
 }
 
 
 function OnGUI () {
 
 display_1.text = "Magic " + currentmagic + " / " + maxmagic;
 
 
 }