Horizontal Slider

I'm trying to implement a slider in the Main Menu that adjusts the degree to which the camera shakes. The menu has a Play Game, Quit, and slider.

Here's my code for the slider:

 using UnityEngine;
 using System.Collections;
 
 public class Shaky_Slider : MonoBehaviour {
     
     public float hSliderValue = 0.0f;
 
     // Use this for initialization
     void Start () {
     
     }
     
     // Update is called once per frame
     void Update () {
     
     }
     
     void OnGUI()
     {
         hSliderValue = GUI.HorizontalSlider(new Rect(525, 980, 200, 30), hSliderValue, 0.0f, 10.0f);
 
         if (hSliderValue == 0.0f)
         {
         iTween.ShakeRotation(gameObject,iTween.Hash("x", 0.0f,"y", 0.0f,"looptype",iTween.LoopType.none,"delay",0.0f,"time",0.0f));    
         }
         if (hSliderValue > 0.0f && hSliderValue < 1.0f)
         {
         iTween.ShakeRotation(gameObject,iTween.Hash("x", 0.1f,"y", 0.05f,"looptype",iTween.LoopType.none,"delay",0.0f,"time",0.0f));
         }
         if (hSliderValue >= 1.0f && hSliderValue < 2.0f)
         {
         iTween.ShakeRotation(gameObject,iTween.Hash("x", 0.2f,"y", 0.1f,"looptype",iTween.LoopType.none,"delay",0.0f,"time",0.0f));
         }
         if (hSliderValue >= 2.0f && hSliderValue < 3.0f)
         {
         iTween.ShakeRotation(gameObject,iTween.Hash("x", 0.3f,"y", 0.3f,"looptype",iTween.LoopType.none,"delay",0.0f,"time",0.0f));
         }
         if (hSliderValue >= 3.0f && hSliderValue < 4.0f)
         {
         iTween.ShakeRotation(gameObject,iTween.Hash("x", 0.4f,"y", 0.5f,"looptype",iTween.LoopType.none,"delay",0.0f,"time",0.0f));
         }
         if (hSliderValue >= 4.0f && hSliderValue < 5.0f)
         {
         iTween.ShakeRotation(gameObject,iTween.Hash("x", 0.5f,"y", 0.9f,"looptype",iTween.LoopType.none,"delay",0.0f,"time",0.0f));
         }
         if (hSliderValue >= 5.0f && hSliderValue < 6.0f)
         {
         iTween.ShakeRotation(gameObject,iTween.Hash("x", 0.6f,"y", 1.3f,"looptype",iTween.LoopType.none,"delay",0.0f,"time",0.0f));
         }
         if (hSliderValue >= 6.0f && hSliderValue < 7.0f)
         {
         iTween.ShakeRotation(gameObject,iTween.Hash("x", 0.7f,"y", 1.7f,"looptype",iTween.LoopType.none,"delay",0.0f,"time",0.0f));
         }
         if (hSliderValue >= 7.0f && hSliderValue < 8.0f)
         {
         iTween.ShakeRotation(gameObject,iTween.Hash("x", 0.8f,"y", 2.1f,"looptype",iTween.LoopType.none,"delay",0.0f,"time",0.0f));
         }
         if (hSliderValue >= 8.0f && hSliderValue < 9.0f)
         {
         iTween.ShakeRotation(gameObject,iTween.Hash("x", 0.9f,"y", 2.5f,"looptype",iTween.LoopType.none,"delay",0.0f,"time",0.0f));
         }
         if (hSliderValue >= 9.0f && hSliderValue <= 10.0f)
         {
         iTween.ShakeRotation(gameObject,iTween.Hash("x", 1.0f,"y", 2.9f,"looptype",iTween.LoopType.none,"delay",0.0f,"time",0.0f));
         }
     }
 }

When I adjust the bar in the menu, the camera changes its degree of shakiness accordingly. However, the problem is that the camera shakes in the menu scene. What do I have to do so that the camera shakes in the scene. Right now, I have the script on the Main Camera in the menu scene.

Any assistance is appreciated. Thank you for your time.