diff --git a/AsbCloudWebApi.Tests/Background/PeriodicBackgroundWorkerTest.cs b/AsbCloudWebApi.Tests/Background/PeriodicBackgroundWorkerTest.cs
index 2701c26e..9fc0f6d9 100644
--- a/AsbCloudWebApi.Tests/Background/PeriodicBackgroundWorkerTest.cs
+++ b/AsbCloudWebApi.Tests/Background/PeriodicBackgroundWorkerTest.cs
@@ -67,10 +67,12 @@ public class PeriodicBackgroundWorkerTest
     {
         var expectadResult = 42;
         var result = 0;
+        using var semaphore = new SemaphoreSlim(0, 1);
 
         Task workAction(string id, IServiceProvider services, Action<string, double?> callback, CancellationToken token)
         {
             result = expectadResult;
+            semaphore.Release();
             return Task.CompletedTask;
         }
         var goodWork = Work.CreateByDelegate("", workAction);
@@ -85,12 +87,12 @@ public class PeriodicBackgroundWorkerTest
         service.Add(badWork, TimeSpan.FromSeconds(2));
         service.Add(goodWork, TimeSpan.FromSeconds(2));
 
-        await Task.Delay(TimeSpan.FromMilliseconds(256));
+        await semaphore.WaitAsync(4_100);
 
         //assert
-        Assert.Equal(expectadResult, result);
         Assert.Equal(1, badWork.CountErrors);
         Assert.Equal(1, goodWork.CountComplete);
         Assert.Equal(1, goodWork.CountStart);
+        Assert.Equal(expectadResult, result);
     }
 }