2D Rougelike Tutorial-Part 13 -Music Will Not Play

I'm on part 13 of the 2d rougelike tutorial. I did every thing the tutorial said and music wont play.

[code=CSharp]

using UnityEngine; using System.Collections;

public class SoundManager : MonoBehaviour { public AudioSource soundEffects; public AudioSource backgroundMusic;

 public float lowPitch = .95f;
 public float highPitch = 1.95f;
 public static SoundManager instance = null;

 // Use this for initialization
 void Awake () {
     if (instance = null)
         instance = this;

     else if (instance != this)
         Destroy(gameObject);


     DontDestroyOnLoad(gameObject);


     
 }

 public void PlaySingle(AudioClip clip)
 {
     soundEffects.clip = clip;
     soundEffects.Play();
 }

 public void RandomizeMusic(params AudioClip[] clips)
 {
     int randomIndex = Random.Range(0, clips.Length);
     float randomPitch = Random.Range(lowPitch, highPitch);

     soundEffects.pitch = randomPitch;
     soundEffects.clip = clips[randomIndex]; 
     soundEffects.Play();


 }
 
 // Update is called once per frame
 void Update () {
 
 }

}

[code/]