diff --git a/src/main/java/net/openhft/chronicle/map/NodeDiscoveryHostPortBroadcaster.java b/src/main/java/net/openhft/chronicle/map/NodeDiscoveryHostPortBroadcaster.java
index ed88341cd..88a6f6eea 100644
--- a/src/main/java/net/openhft/chronicle/map/NodeDiscoveryHostPortBroadcaster.java
+++ b/src/main/java/net/openhft/chronicle/map/NodeDiscoveryHostPortBroadcaster.java
@@ -267,6 +267,8 @@ class BytesExternalizableImpl implements BytesExternalizable {
         this.allNodes = allNodes;
     }
 
+    private final AtomicBoolean modificationsComplete = new AtomicBoolean(true);
+
     /**
      * this is used to tell nodes that are connecting to us which host and ports are in our grid, along with
      * all the identifiers.
@@ -277,6 +279,8 @@ class BytesExternalizableImpl implements BytesExternalizable {
     @Override
     public void writeExternalBytes(@NotNull Bytes destination) {
 
+        modificationsComplete.set(true);
+
         if (bootstrapRequired.getAndSet(false)) {
             //destination.write(BOOTSTRAP_BYTES);
             BOOTSTRAP_BYTES.clear();
@@ -303,7 +307,8 @@ class BytesExternalizableImpl implements BytesExternalizable {
         destination.writeUnsignedShort((int) bytes.remaining());
         destination.write(bytes);
 
-
+        if (!(modificationsComplete.get()))
+            modificationNotifier.onChange();
     }
 
     @Override
@@ -311,7 +316,7 @@ class BytesExternalizableImpl implements BytesExternalizable {
 
         if (isBootstrap(source)) {
             System.out.println("received Bootstrap");
-            //modificationNotifier.onChange();
+            onChange();
             return;
         }
 
@@ -352,6 +357,11 @@ class BytesExternalizableImpl implements BytesExternalizable {
 
     }
 
+    private void onChange() {
+        modificationsComplete.set(false);
+        modificationNotifier.onChange();
+    }
+
 
     /**
      * @param source
@@ -414,18 +424,18 @@ class BytesExternalizableImpl implements BytesExternalizable {
 
     public void sendBootStrap() {
         bootstrapRequired.set(true);
+        onChange();
     }
 
     public void add(InetSocketAddress interfaceAddress) {
         allNodes.add(interfaceAddress);
-        modificationNotifier.onChange();
-
+        onChange();
     }
 
 
     public void add(byte identifier) {
         allNodes.activeIdentifierBitSet().set(identifier);
-        modificationNotifier.onChange();
+        onChange();
     }
 
 }
\ No newline at end of file
diff --git a/src/test/java/net/openhft/chronicle/map/NodeDiscoveryHostPortBroadcasterTest.java b/src/test/java/net/openhft/chronicle/map/NodeDiscoveryHostPortBroadcasterTest.java
index 3226199c7..4dc213935 100644
--- a/src/test/java/net/openhft/chronicle/map/NodeDiscoveryHostPortBroadcasterTest.java
+++ b/src/test/java/net/openhft/chronicle/map/NodeDiscoveryHostPortBroadcasterTest.java
@@ -47,4 +47,31 @@ public class NodeDiscoveryHostPortBroadcasterTest extends TestCase {
     }
 
 
+
+    @Test
+    public void testJustListen() throws IOException, InterruptedException {
+
+        final UdpReplicationConfig udpConfig = UdpReplicationConfig
+                .simple(Inet4Address.getByName("255.255.255.255"), 1235);
+
+        final Bytes identifierBitSetBits = new ByteBufferBytes(ByteBuffer.allocate(128 / 8));
+
+        final RemoteNodes remoteNodes = new RemoteNodes(identifierBitSetBits);
+
+        BytesExternalizableImpl externalizable = new BytesExternalizableImpl(remoteNodes);
+
+
+        final NodeDiscoveryHostPortBroadcaster nodeDiscoveryHostPortBroadcaster
+                = new NodeDiscoveryHostPortBroadcaster(udpConfig, 1024, externalizable);
+
+        externalizable.setModificationNotifier(nodeDiscoveryHostPortBroadcaster);
+
+
+        Thread.sleep(10000000);
+
+
+
+
+    }
+
 }