Invoking Windows Multimedia timer results to hang

I am on Windows 10, Unity Editor 2018.3.12f1

I have a requirement for very fast (500 Hz) and precise updates, "independent" from the Unity main thread. I am targeting windows desktop only, so the Multimedia Timers seemed as a good (the only?) fit. However I witness some weird crashes.
When in Editor, when I press the play button, my sample game seems to be working correctly (ie prints in the Debug console, and with great precision when I used stopwatch to measure), but when i stop the game and try to run it again, the Editor hangs.

When i build and play, again everything seems normal (no debug messages there of course), but when i attempt to close the program via the 'X' button it hangs again.

I tried this library which also includes a working example, and I also created this very simple mono behaviour to test it but with same results:

 using UnityEngine;
 using System.Threading;
 using System.Runtime.InteropServices;
 using System;
 
 public class MultimediaTimer : MonoBehaviour
 {
     private UInt32 userCtx = 0;
    
     void Start()
     {
         // Run();
         Thread r = new Thread(() => Run());
         r.Start();
     }
 
     void Run()
     {
         MultimediaTimerCallback Callback = new MultimediaTimerCallback(TimerCallbackMethod);
         uint timerId = TimeSetEvent(100, 5, Callback, ref userCtx, 1);
         Thread.Sleep(1000);
         TimeKillEvent(timerId);
     }
 
     private static void TimerCallbackMethod(uint id, uint msg, ref uint userCtx, uint rsv1, uint rsv2)
     {
         Debug.Log("Hi");
     }
 
     private delegate void MultimediaTimerCallback(UInt32 id, UInt32 msg, ref UInt32 userCtx, UInt32 rsv1, UInt32 rsv2);
 
     [DllImport("winmm.dll", EntryPoint = "timeSetEvent")]
     private static extern UInt32 TimeSetEvent(UInt32 msDelay, UInt32 msResolution, MultimediaTimerCallback callback, ref UInt32 userCtx, UInt32 eventType);
 
     [DllImport("winmm.dll", EntryPoint = "timeKillEvent")]
     private static extern UInt32 TimeKillEvent(UInt32 uTimerId);
 }
 

My question is very simple. Is it possible to reliably call the multimedia timer from a Unity program? And if not could someone explain this behaviour I observe? I could encapsulate my timer logic in a separate process and use some form of IPC to achieve my requirement, but I would prefer for convenience to stay withing Unity. (Of course if you know any alternatives, by all means do say them)