diff --git a/lib/zeromq_ascoltatore.js b/lib/zeromq_ascoltatore.js
index 5c12689..922593e 100644
--- a/lib/zeromq_ascoltatore.js
+++ b/lib/zeromq_ascoltatore.js
@@ -34,12 +34,12 @@ function ZeromqAscoltatore(opts) {
   this._opts.delay = this._opts.delay || 5;
   this._opts.zmq = this._opts.zmq || require("zmq");
 
+  this._connectedControls = [];
+
   this._ascoltatore = new TrieAscoltatore(opts);
   this._startSubs();
   this._startPub();
   this._startControl();
-
-  this._connectedControls = [];
 }
 
 /**
@@ -122,8 +122,13 @@ ZeromqAscoltatore.prototype._startControl = function() {
       }, 250);
 
       that._control_conn.on("message", function(data) {
-        debug("received connect response from " + data);
-        that._connectSub(data);
+        var dest = String(data)
+        debug("received connect response from " + dest);
+        if (that._sub_conns.findIndex(function (conn) {
+          return conn.port === dest;
+        }) === -1) {
+          that._connectSub(dest);
+        }
       });
     });
   }