diff --git a/src/user_interface.cc b/src/user_interface.cc
index e3ee6a8..037dd5d 100644
--- a/src/user_interface.cc
+++ b/src/user_interface.cc
@@ -49,10 +49,19 @@ namespace pEp {
             _throw_status(status);
         }
 
-        SYNC_EVENT UserInterface::retrieve_next_sync_event(void *management)
+        SYNC_EVENT UserInterface::retrieve_next_sync_event(void *management, time_t threshold)
         {
-            while (adapter.queue().empty())
+            time_t started = time(nullptr);
+            while (adapter.queue().empty()) {
+                int i = 0;
+                ++i;
+                if (i > 10) {
+                    if (time(nullptr) > started + threshold)
+                        break;
+                    i = 0;
+                }
                 nanosleep((const struct timespec[]){{0, 100000000L}}, NULL);
+            }
             return adapter.queue().pop_front();
         }
 
diff --git a/src/user_interface.hh b/src/user_interface.hh
index 115bff8..a2d52f4 100644
--- a/src/user_interface.hh
+++ b/src/user_interface.hh
@@ -28,7 +28,7 @@ namespace pEp {
             protected:
                 static PEP_STATUS _notifyHandshake(void *obj, pEp_identity *me,
                         pEp_identity *partner, sync_handshake_signal signal);
-                static SYNC_EVENT retrieve_next_sync_event( void *management);
+                static SYNC_EVENT retrieve_next_sync_event(void *management, time_t threshold);
         };
 
         class UserInterface_callback : public UserInterface {