diff --git a/Makefile b/Makefile
index 6400e06..ee0c9c1 100644
--- a/Makefile
+++ b/Makefile
@@ -31,6 +31,10 @@ ifneq ($(TEST),)
 TESTARGS := $(TESTARGS) -run $(TEST)
 endif
 
+ifneq ($(COUNT),)
+TESTARGS := $(TESTARGS) -count $(COUNT)
+endif
+
 hook:
 	[ ! -d "$(CURDIR)/.git/hooks" ] || ln -sf "$(CURDIR)/scripts/pre-commit.hook" "$(CURDIR)/.git/hooks/pre-commit"
 
diff --git a/src/signaling/backend_server_test.go b/src/signaling/backend_server_test.go
index fa932b5..d3098bc 100644
--- a/src/signaling/backend_server_test.go
+++ b/src/signaling/backend_server_test.go
@@ -936,6 +936,10 @@ func TestBackendServer_ParticipantsUpdateTimeout(t *testing.T) {
 	} else if room.Room.RoomId != roomId {
 		t.Fatalf("Expected room %s, got %s", roomId, room.Room.RoomId)
 	}
+
+	// Give message processing some time.
+	time.Sleep(10 * time.Millisecond)
+
 	if room, err := client2.JoinRoom(ctx, roomId); err != nil {
 		t.Fatal(err)
 	} else if room.Room.RoomId != roomId {
@@ -946,53 +950,7 @@ func TestBackendServer_ParticipantsUpdateTimeout(t *testing.T) {
 		defer hubRoom.Close()
 	}
 
-	// We will receive "joined" events for all clients. The ordering is not
-	// defined as messages are processed and sent by asynchronous NATS handlers.
-	msg1_1, err := client1.RunUntilMessage(ctx)
-	if err != nil {
-		t.Error(err)
-	}
-	msg1_2, err := client1.RunUntilMessage(ctx)
-	if err != nil {
-		t.Error(err)
-	}
-	msg2_1, err := client2.RunUntilMessage(ctx)
-	if err != nil {
-		t.Error(err)
-	}
-	msg2_2, err := client2.RunUntilMessage(ctx)
-	if err != nil {
-		t.Error(err)
-	}
-
-	if err := client1.checkMessageJoined(msg1_1, hello1.Hello); err != nil {
-		// Ordering is "joined" from client 2, then from client 1
-		if err := client1.checkMessageJoined(msg1_1, hello2.Hello); err != nil {
-			t.Error(err)
-		}
-		if err := client1.checkMessageJoined(msg1_2, hello1.Hello); err != nil {
-			t.Error(err)
-		}
-	} else {
-		// Ordering is "joined" from client 1, then from client 2
-		if err := client1.checkMessageJoined(msg1_2, hello2.Hello); err != nil {
-			t.Error(err)
-		}
-	}
-	if err := client2.checkMessageJoined(msg2_1, hello1.Hello); err != nil {
-		// Ordering is "joined" from client 2, then from client 1
-		if err := client2.checkMessageJoined(msg2_1, hello2.Hello); err != nil {
-			t.Error(err)
-		}
-		if err := client2.checkMessageJoined(msg2_2, hello1.Hello); err != nil {
-			t.Error(err)
-		}
-	} else {
-		// Ordering is "joined" from client 1, then from client 2
-		if err := client2.checkMessageJoined(msg2_2, hello2.Hello); err != nil {
-			t.Error(err)
-		}
-	}
+	WaitForUsersJoined(ctx, t, client1, hello1, client2, hello2)
 
 	var wg sync.WaitGroup
 
diff --git a/src/signaling/hub_test.go b/src/signaling/hub_test.go
index 3205bbc..4baae61 100644
--- a/src/signaling/hub_test.go
+++ b/src/signaling/hub_test.go
@@ -1221,6 +1221,10 @@ func TestClientMessageToRoom(t *testing.T) {
 	} else if room.Room.RoomId != roomId {
 		t.Fatalf("Expected room %s, got %s", roomId, room.Room.RoomId)
 	}
+
+	// Give message processing some time.
+	time.Sleep(10 * time.Millisecond)
+
 	if room, err := client2.JoinRoom(ctx, roomId); err != nil {
 		t.Fatal(err)
 	} else if room.Room.RoomId != roomId {
@@ -1665,6 +1669,10 @@ func TestRoomParticipantsListUpdateWhileDisconnected(t *testing.T) {
 	} else if room.Room.RoomId != roomId {
 		t.Fatalf("Expected room %s, got %s", roomId, room.Room.RoomId)
 	}
+
+	// Give message processing some time.
+	time.Sleep(10 * time.Millisecond)
+
 	if room, err := client2.JoinRoom(ctx, roomId); err != nil {
 		t.Fatal(err)
 	} else if room.Room.RoomId != roomId {
@@ -1940,6 +1948,10 @@ func TestClientSendOfferPermissions(t *testing.T) {
 	} else if room.Room.RoomId != roomId {
 		t.Fatalf("Expected room %s, got %s", roomId, room.Room.RoomId)
 	}
+
+	// Give message processing some time.
+	time.Sleep(10 * time.Millisecond)
+
 	if room, err := client2.JoinRoom(ctx, roomId); err != nil {
 		t.Fatal(err)
 	} else if room.Room.RoomId != roomId {