diff --git a/src/core/Akka.Cluster.Tests/ClusterSpec.cs b/src/core/Akka.Cluster.Tests/ClusterSpec.cs
index 65d9f419074..9c735833c41 100644
--- a/src/core/Akka.Cluster.Tests/ClusterSpec.cs
+++ b/src/core/Akka.Cluster.Tests/ClusterSpec.cs
@@ -270,11 +270,11 @@ await WithinAsync(TimeSpan.FromSeconds(10), async () =>
                 LeaderActions(); // Exiting --> Removed
 
                 // Member should leave even a task was cancelled
-                ExpectMsg<ClusterEvent.MemberRemoved>().Member.Address.Should().Be(_selfAddress);
+                (await ExpectMsgAsync<ClusterEvent.MemberRemoved>()).Member.Address.Should().Be(_selfAddress);
 
                 // Second task should complete (not cancelled)
                 await AwaitConditionAsync(() => Task.FromResult(task2.IsCompleted && !task2.IsCanceled), null, "Task should be completed, but not cancelled.");
-            }, cancellationToken: cts.Token);
+            });
 
             // Subsequent LeaveAsync() tasks expected to complete immediately (not cancelled)
             var task3 = _cluster.LeaveAsync();
@@ -313,7 +313,7 @@ await AwaitAssertAsync(() =>
             }
             finally
             {
-                Shutdown(sys2);
+                await ShutdownAsync(sys2);
             }
         }
 
@@ -374,7 +374,7 @@ await Awaiting(async () =>
             }
             finally
             {
-                Shutdown(sys);
+                await ShutdownAsync(sys);
             }
         }
 
@@ -435,7 +435,7 @@ await Awaiting(async () =>
             }
             finally
             {
-                Shutdown(sys);
+                await ShutdownAsync(sys);
             }
         }
 
@@ -481,7 +481,7 @@ public async Task A_cluster_must_leave_via_CoordinatedShutdownRun()
             }
             finally
             {
-                Shutdown(sys2);
+                await ShutdownAsync(sys2);
             }
         }
 
@@ -518,7 +518,7 @@ public async Task A_cluster_must_leave_via_CoordinatedShutdownRun_when_member_st
             }
             finally
             {
-                Shutdown(sys2);
+                await ShutdownAsync(sys2);
             }
         }
 
@@ -552,7 +552,7 @@ public async Task A_cluster_must_terminate_ActorSystem_via_leave_CoordinatedShut
             }
             finally
             {
-                Shutdown(sys2);
+                await ShutdownAsync(sys2);
             }
         }
 
@@ -585,7 +585,7 @@ public async Task A_cluster_must_terminate_ActorSystem_via_Down_CoordinatedShutd
             }
             finally
             {
-                Shutdown(sys3);
+                await ShutdownAsync(sys3);
             }
         }
     }