Audio object occlusion in Unity with WwiseObjectOcclusion. Fires a raycast when player enters a sphere collider range and detects if objects are between player and item. If so, occlusion is applied.

WwiseObjectOcclusion.cs

using UnityEngine;

////////////////////////////////////////////////////////////////////////
//
// Adapted and modified from the Occlusion Script from Cujo Sound video "Wwise and Unity - Basic Raycasting To Create Occlusion Parameters" 
//
////////////////////////////////////////////////////////////////////////

//Uses Logger.cs, there's a commented version using the Unity Debugger wrapped in a region below

public class WwiseObjectOcclusion : MonoBehaviour
{
#if UNITY_EDITOR
    public bool DebugScript = false;
#endif
    public bool IsInteractable = false;
    public GameObject AudioListener;
    public AK.Wwise.RTPC[] OcclusionsRTPC;
    public float SetLowPassMax = 1;
    public float SetVolumeMax = 1;
    public string NameOfListener = "CameraBrain";
    public string OmitTypeOccluder; // change to array if multiple and adjust code

    private bool lastOcclusionState = false;
    private float maxDistanceOcclusion;
    private SphereCollider sphereCollider;
    private AK.Wwise.RTPC setRTPCLoPass;
    private AK.Wwise.RTPC setRTPCVolume;

    private void Awake()
    {
        if (!enabled)
        {
            Destroy(this);
            return;
        }

        SetUpChecks();
        sphereCollider = GetComponent<SphereCollider>();
        maxDistanceOcclusion = sphereCollider.radius;
    }

    private void SetUpChecks()
    {
        if (OcclusionsRTPC.Length == 2)
        {
            setRTPCLoPass = OcclusionsRTPC[0];
            setRTPCVolume = OcclusionsRTPC[1];

            setRTPCLoPass.SetValue(gameObject, 0);
            setRTPCVolume.SetValue(gameObject, 0);
        }
        else if (OcclusionsRTPC.Length > 2)
        {
            setRTPCLoPass = OcclusionsRTPC[0];
            setRTPCVolume = OcclusionsRTPC[1];

            setRTPCLoPass.SetValue(gameObject, 0);
            setRTPCVolume.SetValue(gameObject, 0);

            Logger.Log($"Remember to set up the additional RTPC's within the OcclusionCheck() function of {this.name}.");
        }
        else
        {
            Logger.LogError($"Set RTPC array with at least 2 parameters at {this.name}. Returning");
            enabled = false;
            return;
        }
    }

    private void Start()
    {
        if (AudioListener == null || sphereCollider == null)
        {
            if (DebugScript)
                Logger.LogError($"WwiseObjectOcclusion is returning, AudioListener or sphereCollider aren't properly set on {this.name}");
            enabled = false;
            return;
        }

        setRTPCLoPass.SetValue(gameObject, 0);
        setRTPCVolume.SetValue(gameObject, 0);

        AkSoundEngine.RegisterGameObj(gameObject);
    }

    private void FixedUpdate()
    {
        OcclusionCheck();

        if (IsInteractable)
            IsOneShotInteractable();
    }

    void OcclusionCheck()
    {
        bool currentOcclusionState = false;
        Vector3 direction = AudioListener.transform.position - transform.position;
        float distanceToPlayer = direction.magnitude;  // Calculate the distance to the player

        if (distanceToPlayer <= maxDistanceOcclusion)  // Check if the player is within the occlusion range
        {
            if (DebugScript)
                Logger.Log("Player is within range");

            if (Physics.Raycast(transform.position, direction, out RaycastHit outInfo, maxDistanceOcclusion))
            {
                if (DebugScript)
                    Logger.Log(outInfo.collider.gameObject.name);

                if (outInfo.collider.gameObject.name != NameOfListener && !outInfo.collider.gameObject.name.Contains(OmitTypeOccluder))
                {
                    currentOcclusionState = true;

                    if (lastOcclusionState != currentOcclusionState)
                    {
                        setRTPCLoPass.SetValue(gameObject, SetLowPassMax);
                        setRTPCVolume.SetValue(gameObject, SetVolumeMax);

                        lastOcclusionState = currentOcclusionState;

                        if (DebugScript)
                            Logger.Log("Occluding");
                    }
                    
                }
                else
                {
                    currentOcclusionState = false;

                    if (lastOcclusionState != currentOcclusionState)
                    {
                        setRTPCLoPass.SetValue(gameObject, 0);
                        setRTPCVolume.SetValue(gameObject, 0);

                        lastOcclusionState = currentOcclusionState;

                        if (DebugScript)
                            Logger.Log("Not Occluding");
                    }
                }

                if (DebugScript)
                    Logger.Log($"lastOcclusionState is {lastOcclusionState}");
            }

        }
        else
        {
            if (DebugScript)
                Logger.Log($"Player is beyond {this.name} occlusion range");

            if (DebugScript)
                Logger.Log($"lastOcclusionState is {lastOcclusionState}");

            return;
        }
    }

    private void IsOneShotInteractable()
    {
        Animator objectAnimator = GetComponentInParent<Animator>();
        bool animatorState = objectAnimator.GetBool("Open");

        if (DebugScript)
            Logger.Log($"Animator state on {this.name} is {animatorState}");

        if (animatorState)
        {
            AkSoundEngine.UnregisterGameObj(gameObject);
            Destroy(GetComponent<AkGameObj>());
            Destroy(GetComponent<Rigidbody>());
            Destroy(this);
        }
    }
}

#region UnityLogScript

//using UnityEngine;
//using Debug = UnityEngine.Debug;

////////////////////////////////////////////////////////////////////////
//
// Adapted and modified from the Occlusion Script from Cujo Sound video "Wwise and Unity - Basic Raycasting To Create Occlusion Parameters" 
//
////////////////////////////////////////////////////////////////////////

////[RequireComponent(typeof(SphereCollider))]
//public class WwiseObjectOcclusion : MonoBehaviour
//{

//#if UNITY_EDITOR
//    public bool DebugScript = false;
//#endif
//    public bool IsInteractable = false;
//    public GameObject AudioListener;

//    [Tooltip("Index 0: Set LowPass. Index 1: Set Volume")]
//    public AK.Wwise.RTPC[] OcclusionsRTPC;

//    public float SetLowPassMax = 1;
//    public float SetVolumeMax = 1;
//    public string NameOfListener = "CameraBrain";
//    public string OmitTypeOccluder; // change to array if multiple and adjust code

//    private float maxDistanceOcclusion;
//    private SphereCollider sphereCollider;

//    private AK.Wwise.RTPC setRTPCLoPass;
//    private AK.Wwise.RTPC setRTPCVolume;

//    private void Awake()
//    {
//        if (!enabled)
//        {
//            Destroy(this);
//            return;
//        }

//        SetUpChecks();
//        sphereCollider = GetComponent<SphereCollider>();
//        maxDistanceOcclusion = sphereCollider.radius;
//    }

//    private void SetUpChecks()
//    {
//        if (OcclusionsRTPC.Length == 2)
//        {
//            setRTPCLoPass = OcclusionsRTPC[0];
//            setRTPCVolume = OcclusionsRTPC[1];

//            setRTPCLoPass.SetValue(gameObject, 0);
//            setRTPCVolume.SetValue(gameObject, 0);
//        }
//        else if (OcclusionsRTPC.Length > 2)
//        {
//            setRTPCLoPass = OcclusionsRTPC[0];
//            setRTPCVolume = OcclusionsRTPC[1];

//            setRTPCLoPass.SetValue(gameObject, 0);
//            setRTPCVolume.SetValue(gameObject, 0);
//#if UNITY_EDITOR
//            Debug.Log($"Remember to set up the additional RTPC's within the OcclusionCheck() function of {this.name}.");
//#endif
//        }
//        else
//        {
//#if UNITY_EDITOR
//            Debug.LogError($"Set RTPC array with at least 2 parameters at {this.name}. Returning");
//#endif
//            enabled = false;
//            return;
//        }
//    }

//    private void Start()
//    {
//        if (AudioListener == null || sphereCollider == null)
//        {
//#if UNITY_EDITOR
//            if (DebugScript)
//                Debug.LogError($"WwiseObjectOcclusion is returning, AudioListener or sphereCollider aren't properly set on {this.name}");
//#endif
//            enabled = false;
//            return;
//        }

//        AkSoundEngine.RegisterGameObj(gameObject);

//    }

//    private void FixedUpdate()
//    {
//        OcclusionCheck();

//        if (IsInteractable)
//            IsOneShotInteractable();
//    }


//    void OcclusionCheck()
//    {
//        Vector3 direction = AudioListener.transform.position - transform.position;
//        float distanceToPlayer = direction.magnitude;  // Calculate the distance to the player

//        if (distanceToPlayer <= maxDistanceOcclusion)  // Check if the player is within the occlusion range
//        {
//#if UNITY_EDITOR
//            if (DebugScript)
//                Debug.Log("Player is within range");
//#endif

//            if (Physics.Raycast(transform.position, direction, out RaycastHit outInfo, maxDistanceOcclusion))
//            {
//#if UNITY_EDITOR
//                if (DebugScript)
//                    Debug.Log(outInfo.collider.gameObject.name);
//#endif

//                if (outInfo.collider.gameObject.name != NameOfListener && !outInfo.collider.gameObject.name.Contains(OmitTypeOccluder))
//                {
//#if UNITY_EDITOR
//                    if (DebugScript)
//                        Debug.Log("Occluding");
//#endif

//                    setRTPCLoPass.SetValue(gameObject, SetLowPassMax);
//                    setRTPCVolume.SetValue(gameObject, SetVolumeMax);
//                }
//                else
//                {
//#if UNITY_EDITOR
//                    if (DebugScript)
//                        Debug.Log("Not Occluding");
//#endif

//                    setRTPCLoPass.SetValue(gameObject, 0);
//                    setRTPCVolume.SetValue(gameObject, 0);
//                }
//            }
//        }
//        else
//        {
//#if UNITY_EDITOR
//            if (DebugScript)
//                Debug.Log($"Player is beyond {this.name} occlusion range");
//#endif

//            return;

//        }
//    }

//    /// <summary>
//    /// Configure to your project
//    /// </summary>
//    private void IsOneShotInteractable()
//    {
//        Animator objectAnimator = GetComponentInParent<Animator>(); //Or simply "GetComponent<Type>()"
//        bool animatorState = objectAnimator.GetBool("Open");

//#if UNITY_EDITOR
//        if (DebugScript)
//            Debug.Log($"Animator state on {this.name} is {animatorState}");
//#endif

//        if (animatorState)
//        {
//            Destroy(this);
//        }
//    }

//}
#endregion