diff --git a/slsReceiverSoftware/src/Implementation.h b/slsReceiverSoftware/src/Implementation.h
index 6f513868a..f3e5ae8ce 100644
--- a/slsReceiverSoftware/src/Implementation.h
+++ b/slsReceiverSoftware/src/Implementation.h
@@ -296,7 +296,7 @@ class Implementation : private virtual slsDetectorDefs {
     // network configuration (UDP)
     int numUDPInterfaces{1};
     std::array<std::string,MAX_NUMBER_OF_LISTENING_THREADS>eth;
-    std::array<uint32_t,MAX_NUMBER_OF_LISTENING_THREADS> udpPortNum{DEFAULT_UDP_PORTNO, DEFAULT_UDP_PORTNO+1};
+    std::array<uint32_t,MAX_NUMBER_OF_LISTENING_THREADS> udpPortNum{{DEFAULT_UDP_PORTNO, DEFAULT_UDP_PORTNO+1}};
     int64_t udpSocketBufferSize{0};
     int64_t actualUDPSocketBufferSize{0};