diff --git a/src/WebSockets.cpp b/src/WebSockets.cpp
index b3ad336..ce4017b 100644
--- a/src/WebSockets.cpp
+++ b/src/WebSockets.cpp
@@ -254,7 +254,11 @@ void WebSockets::handleWebsocket(WSclient_t * client) {
     }
 
     if(mask) {
-        client->tcp.read(maskKey, 4);
+        if(!readWait(client, maskKey, 4)) {
+            //timeout
+            clientDisconnect(client, 1002);
+            return;
+        }
     }
 
     if(payloadLen > 0) {
diff --git a/src/WebSockets.h b/src/WebSockets.h
index b52f135..44a8c6e 100644
--- a/src/WebSockets.h
+++ b/src/WebSockets.h
@@ -44,7 +44,7 @@
 #endif
 
 #define WEBSOCKETS_MAX_DATA_SIZE  (15*1024)
-#define WEBSOCKETS_TCP_TIMEOUT    (1000)
+#define WEBSOCKETS_TCP_TIMEOUT    (1500)
 
 typedef enum {
     WSC_NOT_CONNECTED,
diff --git a/src/WebSocketsClient.cpp b/src/WebSocketsClient.cpp
index dac1308..210bd6b 100644
--- a/src/WebSocketsClient.cpp
+++ b/src/WebSocketsClient.cpp
@@ -218,13 +218,17 @@ void WebSocketsClient::clientDisconnect(WSclient_t * client) {
  */
 bool WebSocketsClient::clientIsConnected(WSclient_t * client) {
 
-    if(client->status != WSC_NOT_CONNECTED && client->tcp.connected()) {
-        return true;
-    }
-
-    if(client->status != WSC_NOT_CONNECTED) {
-        // cleanup
-        clientDisconnect(&_client);
+    if(client->tcp.connected()) {
+        if(client->status != WSC_NOT_CONNECTED) {
+            return true;
+        }
+    } else {
+        // client lost
+        if(client->status != WSC_NOT_CONNECTED) {
+            DEBUG_WEBSOCKETS("[WS-Client] connection lost.\n");
+            // do cleanup
+            clientDisconnect(client);
+        }
     }
     return false;
 }
diff --git a/src/WebSocketsServer.cpp b/src/WebSocketsServer.cpp
index 0982b35..f8ca998 100644
--- a/src/WebSocketsServer.cpp
+++ b/src/WebSocketsServer.cpp
@@ -302,13 +302,17 @@ void WebSocketsServer::clientDisconnect(WSclient_t * client) {
  */
 bool WebSocketsServer::clientIsConnected(WSclient_t * client) {
 
-    if(client->status != WSC_NOT_CONNECTED && client->tcp.connected()) {
-        return true;
-    }
-
-    if(client->status != WSC_NOT_CONNECTED) {
-        // cleanup
-        clientDisconnect(client);
+    if(client->tcp.connected()) {
+        if(client->status != WSC_NOT_CONNECTED) {
+            return true;
+        }
+    } else {
+        // client lost
+        if(client->status != WSC_NOT_CONNECTED) {
+            DEBUG_WEBSOCKETS("[WS-Server][%d] client connection lost.\n", client->num);
+            // do cleanup
+            clientDisconnect(client);
+        }
     }
     return false;
 }