diff --git a/fairmq/test/helper/devices/TestPub.cxx b/fairmq/test/helper/devices/TestPub.cxx
index 13d62bd9..4162e8bc 100644
--- a/fairmq/test/helper/devices/TestPub.cxx
+++ b/fairmq/test/helper/devices/TestPub.cxx
@@ -34,7 +34,11 @@ class Pub : public FairMQDevice
 
             auto msg = FairMQMessagePtr{NewMessage()};
             auto d1 = Send(msg, "data");
-            if (d1 < 0)
+            if (d1 >= 0)
+            {
+                LOG(INFO) << "Sent data: d1 = " << d1;
+            }
+            else
             {
                 LOG(ERROR) << "Failed sending data: d1 = " << d1;
             }
diff --git a/fairmq/test/helper/devices/TestSub.cxx b/fairmq/test/helper/devices/TestSub.cxx
index fae86902..adb8c375 100644
--- a/fairmq/test/helper/devices/TestSub.cxx
+++ b/fairmq/test/helper/devices/TestSub.cxx
@@ -28,13 +28,19 @@ class Sub : public FairMQDevice
         auto r1 = Send(ready, "control");
         if (r1 >= 0)
         {
+            LOG(INFO) << "Sent first control signal";
             auto msg = FairMQMessagePtr{NewMessage()};
             auto d1 = Receive(msg, "data");
             if (d1 >= 0)
             {
+                LOG(INFO) << "Received data";
                 auto ack = FairMQMessagePtr{NewMessage()};
                 auto a1 = Send(ack, "control");
-                if (a1 < 0)
+                if (a1 >= 0)
+                {
+                    LOG(INFO) << "Sent second control signal";
+                }
+                else
                 {
                     LOG(ERROR) << "Failed sending ack signal: a1 = " << a1;
                 }