Error using attribute FMODUnity.EventRef to pick event in inspector

I made a scriptable object, and want a FMOD event selector, using this code.
Is there a bug in EventRefDrawer? Is something wrong with my fmod setup? It plays events from code like it should if I call it using a string. I can see the events when i click the magnifying glass, but nothing gets selected. See the image and gif below.

Unity 2020.1.4 and FMOD fmodstudio20107.unitypackage

using FMODUnity;
using UnityEngine;

namespace _Game.Scripts.BlueGoo.Creatures {
	[CreateAssetMenu(fileName = "CreatureSetting", menuName = "BlueGoo/Creature Setting", order = 0)]
	public class NpcSetting : ScriptableObject {
		public float territoryRadius = 10;
		public FMODEventPlayable fleeSound;

		public FMODEventPlayable hurtSound;


Error in console:

type is not a supported string value
FMODUnity.EventRefDrawer:OnGUI(Rect, SerializedProperty, GUIContent) (at Assets/Plugins/FMOD/src/Editor/EventRefDrawer.cs:93)
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr, Boolean&)

Ok, the issue was I should use a string, not FMODEventPlayable

public string fleeSound;