Camera Slerp rotation Jitter / Stutter when in a hierarchy with a CharacterController parent

Hi everyone,

I've seen quite many similar questions, but none of the solutions remedied my situation. I've actually done these, but no luck: - Changing Update-LateUpdate to FixedUpdate, neutralize the rotation, except when I call this CameraRotate FixedUpdate in its parent FirstPersonController, after moving the FPS character. Also, as I don't use rigidbodies, I have not tried neither interpolation nor extrapolation. - Decreasing Fixed Timestep to 0.01s or less in project settings Time, while decreasing Application.targetFrameRate to 30 fps also maintains the stutter on my J7 galaxy. Decreasing Application.targetFrameRate to 5, eliminates the stutter, but the frame rate would be too low, and the game would run slow. Decreasing Fixed Timestep or TimeScale further results the same. - I have not tried moving the camera out of the player, because that messes up my hierarchy.

The FirstPersonController attached to the root of the player is a standard one with touch controls added. The CameraRotate attached to the camera inside the player is this:

 public class CameraRotate : MonoBehaviour
 {
     public Vector3 targetAngle;
     private float targetZ;
     private Vector3 currentAngle;
     
     void Start()
     {
         targetAngle = Camera.main.transform.eulerAngles;
         targetZ = targetAngle.z;
         currentAngle = transform.eulerAngles;
     }
 
     
     void LateUpdate()
     {
  if (CrossPlatformInputManager.GetAxis("Horizontal") > 0 )
             targetAngle.z = -35f;
         else if (CrossPlatformInputManager.GetAxis("Horizontal") < 0)
             targetAngle.z = 35f;
         else
             targetAngle.z = targetZ;
 transform.rotation = Quaternion.Slerp(transform.rotation, Quaternion.Euler(targetAngle.x, targetAngle.y, targetAngle.z),  Time.smoothDeltaTime);
       
     }

Is there any formula to set the targetFrameRate and Fixed Timestep accordingly?(after turning off the vSyncCount) Any ideas how to remove the stutter?