Manage and toggle background music and mute?

I'm trying to make a button to manage the background music, taking into to consideration if it is muted or not but there's a problem with the script playing the audio clip. Whenever I click the bgm toggle in the option scene I gave to go back to main menu where the script controlling the audio clip is for it to take effect. When I changed the code the mute button started acting weird, playing the audio clip multiple times making it sound distorted. How can I fix my code, to make the bgm toggle and mute button work independently?

 private bool muted;
 private bool BGMstatus;
 private static BgMusicPlayer instance = null;
 public static BgMusicPlayer Instance
 {
     get
     {
         if (instance == null)
         {
             instance = (BgMusicPlayer)FindObjectOfType(typeof(BgMusicPlayer));
         }
         return instance;
     }
 }

 void Awake() {

     if (Instance != this)
     {
         Destroy(gameObject);
     }
     else
     {
         DontDestroyOnLoad(gameObject);
     }

     SoundCheck ();
     BGMSoundCheck ();

// instance = this; // DontDestroyOnLoad(gameObject); }

 void Update () {
 
     SoundCheck ();
     BGMSoundCheck ();

     if(Application.loadedLevelName == "Stage")
         {
             audio.Stop ();
         }


     if(Application.loadedLevelName == "Main Menu" && !muted && !audio.isPlaying)
     {
         if(!BGMstatus)
         {
             audio.Play ();
         }
         else if (BGMstatus)
         {
             audio.Stop ();
         }
     }

     else if(Application.loadedLevelName == "Main Menu" && muted && audio.isPlaying)
     {
         if(BGMstatus)
         {
             audio.Stop ();
         }
         else if (!BGMstatus)
         {
             audio.Play ();
         }
     }

 }

 void SoundCheck ()
 {
     if (PlayerPrefs.GetInt ("AudioIsMuted") == 1) 
     {
         muted = true;
     } 
     else if (PlayerPrefs.GetInt ("AudioIsMuted") == 0)
     {
         muted = false;
     }
 }

 void BGMSoundCheck ()
 {
     if (PlayerPrefs.GetInt ("BGMIsMuted") == 1) 
     {
         BGMstatus = true;
     } 
     else if (PlayerPrefs.GetInt ("BGMIsMuted") == 0)
     {
         BGMstatus = false;
     }
     
 }