diff --git a/protocol/enttec/dmx-usb-pro/pro.h b/protocol/enttec/dmx-usb-pro/pro.h
index 21d55c9..3a55d5a 100644
--- a/protocol/enttec/dmx-usb-pro/pro.h
+++ b/protocol/enttec/dmx-usb-pro/pro.h
@@ -114,9 +114,9 @@ struct MsgReprogramFirmware
 {
   MsgReprogramFirmware() : MessageData(1) {};
 
-  size_t streamSize() const override { return 0; };
-  void iStream(std::shared_ptr<bufferstream>) override {};
-  void oStream(std::shared_ptr<bufferstream>) const override{};
+  virtual size_t streamSize() const override { return 0; };
+  virtual void iStream(std::shared_ptr<bufferstream>) override {};
+  virtual void oStream(std::shared_ptr<bufferstream>) const override{};
 };
 
 
@@ -132,9 +132,9 @@ struct MsgProgramFlashPageRequest
 {
   MsgProgramFlashPageRequest() : MessageData(2) {};
 
-  size_t streamSize() const override { return 64; };
-  void iStream(std::shared_ptr<bufferstream>) override;
-  void oStream(std::shared_ptr<bufferstream>) const override;
+  virtual size_t streamSize() const override { return 64; };
+  virtual void iStream(std::shared_ptr<bufferstream>) override;
+  virtual void oStream(std::shared_ptr<bufferstream>) const override;
 
   uint8_t page[64];                         //!< One page of firmware binary file.
 };
@@ -151,9 +151,9 @@ struct MsgProgramFlashPageReply
 {
   MsgProgramFlashPageReply() : MessageData(2) {};
 
-  size_t streamSize() const override { return 4; };
-  void iStream(std::shared_ptr<bufferstream>) override;
-  void oStream(std::shared_ptr<bufferstream>) const override;
+  virtual size_t streamSize() const override { return 4; };
+  virtual void iStream(std::shared_ptr<bufferstream>) override;
+  virtual void oStream(std::shared_ptr<bufferstream>) const override;
 
   bool success;                             //!< Success character array product
 };
@@ -172,9 +172,9 @@ struct MsgGetWidgetParametersRequest
 {
   MsgGetWidgetParametersRequest() : MessageData(3) {};
 
-  size_t streamSize() const override { return 2; };
-  void iStream(std::shared_ptr<bufferstream>) override;
-  void oStream(std::shared_ptr<bufferstream>) const override;
+  virtual size_t streamSize() const override { return 2; };
+  virtual void iStream(std::shared_ptr<bufferstream>) override;
+  virtual void oStream(std::shared_ptr<bufferstream>) const override;
 
   uint16_t size = 0;                        //!< user configuration size in bytes
 };
@@ -193,9 +193,9 @@ struct MsgGetWidgetParametersReply
 {
   MsgGetWidgetParametersReply() : MessageData(3) {};
 
-  size_t streamSize() const override { return 5 + user_data.size(); };
-  void iStream(std::shared_ptr<bufferstream>) override;
-  void oStream(std::shared_ptr<bufferstream>) const override;
+  virtual size_t streamSize() const override { return 5 + user_data.size(); };
+  virtual void iStream(std::shared_ptr<bufferstream>) override;
+  virtual void oStream(std::shared_ptr<bufferstream>) const override;
 
   union {
     uint16_t version;
@@ -232,9 +232,9 @@ struct MsgSetWidgetParametersRequest
 {
   MsgSetWidgetParametersRequest() : MessageData(4) {};
 
-  size_t streamSize() const override { return 5 + user_data.size(); };
-  void iStream(std::shared_ptr<bufferstream>) override;
-  void oStream(std::shared_ptr<bufferstream>) const override;
+  virtual size_t streamSize() const override { return 5 + user_data.size(); };
+  virtual void iStream(std::shared_ptr<bufferstream>) override;
+  virtual void oStream(std::shared_ptr<bufferstream>) const override;
 
   uint8_t break_time;                       //!< interval count of the DMX output BREAK
   uint8_t mab_time;                         //!< interval count of the DMX output MARK AFTER BREAK
@@ -255,9 +255,9 @@ struct MsgRecievedDmxPacket
 {
   MsgRecievedDmxPacket() : MessageData(5) {};
 
-  size_t streamSize() const override { return 1 + data.size(); };
-  void iStream(std::shared_ptr<bufferstream>) override;
-  void oStream(std::shared_ptr<bufferstream>) const override;
+  virtual size_t streamSize() const override { return 1 + data.size(); };
+  virtual void iStream(std::shared_ptr<bufferstream>) override;
+  virtual void oStream(std::shared_ptr<bufferstream>) const override;
 
   union {
     uint8_t rx_errors;                      //!< When this is 0, the DMX data is valid.
@@ -287,9 +287,9 @@ struct MsgOutputOnlySendDMX
 {
   MsgOutputOnlySendDMX() : MessageData(6) {};
 
-  size_t streamSize() const override { return std::max(data.size(), DMX_LAST_SLOT_MIN + 1); };
-  void iStream(std::shared_ptr<bufferstream>) override;
-  void oStream(std::shared_ptr<bufferstream>) const override;
+  virtual size_t streamSize() const override { return std::max(data.size(), DMX_LAST_SLOT_MIN + 1); };
+  virtual void iStream(std::shared_ptr<bufferstream>) override;
+  virtual void oStream(std::shared_ptr<bufferstream>) const override;
 
   std::vector<uint8_t> data;                //!< DMX data to send, beginning with the start code.
 };
@@ -308,9 +308,9 @@ struct MsgSendRDMData
 {
   MsgSendRDMData() : MessageData(7) {};
 
-  size_t streamSize() const override { return data.size(); };
-  void iStream(std::shared_ptr<bufferstream>) override;
-  void oStream(std::shared_ptr<bufferstream>) const override;
+  virtual size_t streamSize() const override { return data.size(); };
+  virtual void iStream(std::shared_ptr<bufferstream>) override;
+  virtual void oStream(std::shared_ptr<bufferstream>) const override;
 
   std::vector<uint8_t> data;                //!< RDM data to send, beginning with the start code.
 };
@@ -335,9 +335,9 @@ struct MsgRecieveDMXOnChange
 {
   MsgRecieveDMXOnChange() : MessageData(8) {};
 
-  size_t streamSize() const override { return 1; };
-  void iStream(std::shared_ptr<bufferstream>) override;
-  void oStream(std::shared_ptr<bufferstream>) const override;
+  virtual size_t streamSize() const override { return 1; };
+  virtual void iStream(std::shared_ptr<bufferstream>) override;
+  virtual void oStream(std::shared_ptr<bufferstream>) const override;
 
   DMX_RX_MODE mode = RxNotifyAlways;        //!< Always (default), or OnChange
 };
@@ -355,9 +355,9 @@ struct MsgRecievedDMXChanged
 {
   MsgRecievedDMXChanged() : MessageData(9) {};
 
-  size_t streamSize() const override { return 6 + data.size(); };
-  void iStream(std::shared_ptr<bufferstream>) override;
-  void oStream(std::shared_ptr<bufferstream>) const override;
+  virtual size_t streamSize() const override { return 6 + data.size(); };
+  virtual void iStream(std::shared_ptr<bufferstream>) override;
+  virtual void oStream(std::shared_ptr<bufferstream>) const override;
 
   uint8_t start;                            //!< Start changed byte number.
   uint8_t changed[5];                       //!< Changed bit array.
@@ -375,9 +375,9 @@ struct MsgGetWidgetSerialRequest
 {
   MsgGetWidgetSerialRequest() : MessageData(10) {};
 
-  size_t streamSize() const override { return 0; };
-  void iStream(std::shared_ptr<bufferstream>) override {};
-  void oStream(std::shared_ptr<bufferstream>) const override{};
+  virtual size_t streamSize() const override { return 0; };
+  virtual void iStream(std::shared_ptr<bufferstream>) override {};
+  virtual void oStream(std::shared_ptr<bufferstream>) const override{};
 };
 
 
@@ -392,9 +392,9 @@ struct MsgGetWidgetSerialReply
 {
   MsgGetWidgetSerialReply() : MessageData(10) {};
 
-  size_t streamSize() const override { return 4; };
-  void iStream(std::shared_ptr<bufferstream>) override;
-  void oStream(std::shared_ptr<bufferstream>) const override;
+  virtual size_t streamSize() const override { return 4; };
+  virtual void iStream(std::shared_ptr<bufferstream>) override;
+  virtual void oStream(std::shared_ptr<bufferstream>) const override;
 
   uint32_t serial;                          //!< BCD serial number.
 };
@@ -411,9 +411,9 @@ struct MsgSendRDMDiscovery
 {
   MsgSendRDMDiscovery() : MessageData(11) {};
 
-  size_t streamSize() const override { return 38; };
-  void iStream(std::shared_ptr<bufferstream>) override;
-  void oStream(std::shared_ptr<bufferstream>) const override;
+  virtual size_t streamSize() const override { return 38; };
+  virtual void iStream(std::shared_ptr<bufferstream>) override;
+  virtual void oStream(std::shared_ptr<bufferstream>) const override;
 
   uint8_t request[38];                      //!< DISC_UNIQUE_BRANCH RDM request packet to send.
 };