--- a/src/main/java/com/glavsoft/rfb/protocol/ReceiverTask.java	Mon Feb 17 13:56:51 2020 +0900
+++ b/src/main/java/com/glavsoft/rfb/protocol/ReceiverTask.java	Mon Feb 17 17:11:55 2020 +0900
@@ -119,6 +119,7 @@
 
     @Override
     public void run() {
+        int failure = 0;
         isRunning = true;
         if (fullscreenFbUpdateIncrementalRequest != null) {
             fullscreenFbUpdateIncrementalRequest.sendFullScreenRequest(context);
@@ -154,11 +155,13 @@
                         logger.fine("Unsupported server message. Id = " + messageId);
                         continue;
                 }
+                failure = 0;
             } catch (TransportException e) {
                 System.out.println(e.getMessage());
                 System.out.println(e.getCause().getClass().getSimpleName());
                 if (e.getCause().getClass().getSimpleName().equals("SocketTimeoutException")) {
                     sendFrameBufferUpdateRequest();
+                    if (failure++ > 10) stopTask();
                     continue;
                 }
                 logger.severe("Close session : ReceiverTask : " + e.getMessage());
@@ -268,7 +271,7 @@
                 logger.finest(rect.toString() + (0 == numberOfRectangles ? "\n---" : ""));
                 if (decoder != null) {
                     try {
-                        System.out.println(rect);
+                        // System.out.println(rect);
                         decoder.decode(reader, renderer, rect);  // TreeVNC processing here
                         if (rfb.getCuiVersion()) continue;
                         repaintController.repaintBitmap(rect);
@@ -298,7 +301,7 @@
                         screen.port = (int) id;
                         screen.time = flag;
                         screens.add(screen);
-                        System.out.println("screen " + id + ":" + "x=" + x + " y=" + y + "width=" + width + "height=" + height);
+                        // System.out.println("screen " + id + ":" + "x=" + x + " y=" + y + "width=" + width + "height=" + height);
                     }
                     return;
                 } else if (rect.getEncodingType() == EncodingType.DESKTOP_SIZE) {

--- a/src/main/java/jp/ac/u_ryukyu/treevnc/TreeRFBProto.java	Mon Feb 17 13:56:51 2020 +0900
+++ b/src/main/java/jp/ac/u_ryukyu/treevnc/TreeRFBProto.java	Mon Feb 17 17:11:55 2020 +0900
@@ -81,7 +81,7 @@
     private boolean stopBroadcast;
     // multicastBlocking is an internal test flag
     //   perform blocking on TCP connection
-    public boolean multicastBlocking = true;
+    public boolean multicastBlocking = false;
 
     public TreeRFBProto(boolean isTreeManager, ViewerInterface viewer) {
         nets.setMyRfb(this);
@@ -311,10 +311,8 @@
                 writerRunning.set(1);
                 try {
                     // requestThreadNotify(); // send full screen request via fullScreenRequestThread
-
                     // after this, we discard upward packet.
                     new Thread(reader, "upward-packet-processing").start();
-
                     for (; ; ) {
                         LinkedList<ByteBuffer> bufs = c.poll();
                         int inputIndex = 0;
@@ -350,7 +348,7 @@
                 while (inputIndex < bufs.size()) {
                     ByteBuffer b = bufs.get(inputIndex++);
                     os.write(b.array(), b.position(), b.limit());
-                    messageDump(b.array(),b.limit()-b.position(),24, "write to client: ");
+                    // messageDump(b.array(),b.limit()-b.position(),24, "write to client: ");
                 }
                 os.flush();
                 multicastqueue.heapAvailable();