Character Controller PC versus Mac Problem

I have a character controller on my player object. I have my own script that I use to move it. It is very simply. Here are the entries on the controller:

slope limit 45, step offset .1, skin width .1, min move 0, center 0,0,0, radius .5, height 1.3.

Here is the script I use to move it:

 using UnityEngine;
 using System.Collections;
 
 [RequireComponent(typeof(CharacterController))]
 public class MovementScript : MonoBehaviour
 {
     public bool Enabled { get; set; }
     
     public float f_speed;
     public float f_gravity;
     
     private CharacterController controller;
     private Vector3 moveDirection = Vector3.zero;
     
     void Start ()
     {
         controller = GetComponent<CharacterController>();
         Enabled = true;
     }
 
     void Update ()
     {
         if (Enabled)
         {
             if (controller.isGrounded)
             {
                 moveDirection = new Vector3(Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical"));
                 moveDirection = transform.TransformDirection(moveDirection);
                 moveDirection *= f_speed;
 
             }
     
             moveDirection.y -= f_gravity;
             controller.Move(moveDirection * Time.deltaTime);
         }
     }
 }

When I build this on my Mac everything works perfect. If I build an output PC.exe file and run it on the PC then the player tries to go straight up in the air instead of any other direction.

On the Mac if I hit W the character goes forward, S he goes backward, A he slides to the left and D to the right. As I said, he works perfect.

If I build for PC and run it on a PC then he ALWAYS goes UP instead of the direction like on the Mac.

If I open Unity and open the project on the PC I get the same bad results running in the editor. I have added logging on the PC to see if the horizontal and vertical values are correct and they are.

I am running the same version of Unity on the Mac and PC.

What the heck is going on?

EDIT: I just uploaded a test project that demonstrates the problem: Test Project If you Play it on Mac it works fine. If you Play it on Windows it doesn't move as it should.

I also have built a web player version of it. If you go to this on a Mac it works fine. If you try it on Windows it doesn't work. I use Chrome on both. Here is the link: http://www.shatalmic.com/cctest