Unity Component to implement stereo audio panning in 2D

AudioPan2D.cs

using UnityEngine;

public class AudioPan2D : MonoBehaviour
{
    [SerializeField]
    AudioSource audioSource;

    public Transform target;
    
    public float panRangeMax = 1f;

    private void Update()
    {
        if(audioSource == null || target == null) return;
    
        Vector2 dir = target.position - transform.position;
        float distance = dir.magnitude;
        dir.Normalize();
        audioSource.panStereo = Vector2.Dot(Vector2.left, dir) * Mathf.Clamp01(distance / panRangeMax);
    }

    private void OnDrawGizmosSelected()
    {
        Gizmos.DrawWireSphere(transform.position, panRangeMax);
    }
    
    private void Reset()
    {
        audioSource = GetComponent<AudioSource>();
    }
}