Some sounds won't play

The game I'm working on plays different sounds depending on what's going on. This is the script that decides what sound will play:

     public AudioClip lightSwitch;
     public AudioClip ticking;
     public AudioClip winSound;
     public AudioClip loseSound;
 
     public AudioSource source; // The object that will play the sounds
 
     void Start()
     {
         source.GetComponent<AudioSource>();
         source.clip = lightSwitch;
         source.Play();
         Debug.Log("Playing lightSwitch");
     }
 
     void Update()
     {
         if(MGSystem.singelton.play == true)
         {
             source.clip = ticking;
             source.Play();
             Debug.Log("Playing ticking");
         }
         else
         {
             if (MGSystem.singelton.hasWon == true)
             {
                 // hasWon is true when the game starts, so this makes sure the game has ended before playing the sound
                 if(MGSystem.singelton.secondsLeft == 0)
                 {
                     source.clip = winSound;
                     source.Play();
                     Debug.Log("Playing winSound");
                 }
                 else
                 {
                     return;
                 }
             }
             else
             {
                 source.clip = loseSound;
                 source.Play();
                 Debug.Log("Playing loseSound");
             }
         }
     }

The problem is that lightSwitch and winSound will play but ticking and loseSound won't. The debug log will pop up in the console so I know the code itself works, but for some reason those two clips won't play. Does anyone know what I'm doing wrong?