diff --git a/src/sakia/core/net/api/bma/access.py b/src/sakia/core/net/api/bma/access.py
index 9324a38266a973e96746613dd1042329166b878e..fd0fa7ee5b36328753f754a6dbb68eb00689af75 100644
--- a/src/sakia/core/net/api/bma/access.py
+++ b/src/sakia/core/net/api/bma/access.py
@@ -297,10 +297,10 @@ class BmaAccess(QObject):
         .. note:: If one node accept the requests (returns 200),
         the broadcast should be considered accepted by the network.
         """
-        nodes = self._network.online_nodes
+        nodes = self._network.synced_nodes
         replies = []
         if len(nodes) > 0:
-            for node in nodes:
+            for node in random.sample(nodes, 6):
                 logging.debug("Trying to connect to : " + node.pubkey)
                 conn_handler = node.endpoint.conn_handler()
                 req = request(conn_handler, **req_args)
diff --git a/src/sakia/gui/certification.py b/src/sakia/gui/certification.py
index 3ae4f3fafc88510034b93d5b825314019ced983c..4b847b300bf28b50e7a4356b38cfd87730d779a1 100644
--- a/src/sakia/gui/certification.py
+++ b/src/sakia/gui/certification.py
@@ -149,7 +149,6 @@ class CertificationDialog(QObject):
         :rtype: str
         """
         pubkey = None
-        self.ui.button_box.setEnabled(False)
         if self.ui.radio_contact.isChecked():
             for contact in self.account.contacts:
                 if contact['name'] == self.ui.combo_contact.currentText():