diff --git a/src/ATBAPP/DeviceControllerDiag.cpp b/src/ATBAPP/DeviceControllerDiag.cpp
index a0fc647..eab069e 100644
--- a/src/ATBAPP/DeviceControllerDiag.cpp
+++ b/src/ATBAPP/DeviceControllerDiag.cpp
@@ -95,6 +95,9 @@ bool DeviceControllerDiag::isOperatingState()
 
 QSet<DCMachineEvent> DeviceControllerDiag::getCurrentMachineState()
 {
+    // ensure that currentMachineEventSet is delivered here
+    if (this->isRequestRunning) return this->previousMachineEventSet;
+
     return this->machineEventSet;
 }