added boss music transitions, not tested yet

Assets/Scripts/Audio/BackgroundMusic.cs

@@ -35,7 +35,7 @@ public class BackgroundMusic : MonoBehaviour {
 		if (AS[current].timeSamples != preTransitionSample)
 		{
 			inTransition = false;
-			AS[other].volume = 1;
+			AS[1 - current].volume = 1;
 			fadePerSecond = -1;
 			Debug.Log("Music transition complete, playing " + AS[current].clip.name +
 			"\nSample new: " + AS[current].timeSamples + ", Sample old: " + AS[1-current].timeSamples +

Assets/Scripts/Audio/MusicObject.cs

@@ -20,4 +20,11 @@ public class MusicObject : ScriptableObject {
 	public bool isLoop = false;
 	[Tooltip("The non-looped version if this song is looped (required), the looped version otherwise (optional).")]
 	public MusicObject loopCounterpiece;
+    
+    public MusicObject() {}
+    public MusicObject(AudioClip clip)
+    {
+        this.clip = clip;
+        isLoop = false;
+    }
 }

Assets/Scripts/Enemies/BossAI.cs

@@ -54,6 +54,8 @@ public class BossAI : MonoBehaviour
 
     //CameraShake der MainCamera
     public CameraShake cameraShake;
+    private BackgroundMusic bgMusic;
+    
     //Events, die während des Phasenwechsels screen shake den Bildschirm schwarz und wieder sichtbar machen
     public UnityEvent screenShake;
     public UnityEvent fadeToBlack;
@@ -71,7 +73,8 @@ public class BossAI : MonoBehaviour
 	[SerializeField] private AudioSource audioSource;
 	[SerializeField] private SoundVolume soundVolumeHit;
 	[SerializeField] private SoundVolume soundVolumeScream1;
-	[SerializeField] private SoundVolume soundVolumeScream2;
+    [SerializeField] private SoundVolume soundVolumeScream2;
+    [SerializeField] private AudioClip[] music;
 
     private void Awake()
     {
@@ -79,6 +82,7 @@ public class BossAI : MonoBehaviour
         health = bossHealth.healthPoints;
 
         player = GameObject.FindGameObjectWithTag("Player");
+        bgMusic = GameObject.FindGameObjectWithTag("MainCamera").GetComponent<BackgroundMusic>();
 
         shootingPoint = transform.position + horizontalOffset * Vector3.right + verticalOffset * Vector3.up;
 
@@ -160,10 +164,12 @@ public class BossAI : MonoBehaviour
 		if(health == 3)
 		{
 			audioSource.PlayOneShot(soundVolumeScream1.clip, soundVolumeScream1.volume);
+            bgMusic.TransitionTo(new MusicObject(music[1]), 2f);
 		}
 		else if(health == 2)
 		{
 			audioSource.PlayOneShot(soundVolumeScream2.clip, soundVolumeScream2.volume);
+            bgMusic.TransitionTo(new MusicObject(music[2]), 2f);
 		}
 
         yield return new WaitForSeconds(timeBetweenShakeAndFade);