AudioSource not playing sound, Editor crashes?

Hi UnityAnswers,

I am trying to play a sound when the player walks into the cube? At the moment the game crashes when the player collides with the cube?

Any ideas, help, suggestions would be appreciated.

 using UnityEngine;
 using System.Collections;
 using UnityEngine.UI;
 
 public class Trigger : MonoBehaviour 
 {
     public GameObject guiObject;
     private Question1 guiScript;
     public AudioSource collision;
 
     
     void Awake ()
     {
         guiScript = guiObject.GetComponent<Question1> ();
         guiScript.enabled = false; //Turn off the script, so the OnGUI function doesn't draw the question window
     }
 
     void OnTriggerEnter (Collider other)
     {
         if (collision)
             audio.Play();
         guiScript.enabled = true;
         Destroy (this.gameObject);
     }
 }