diff --git a/libraries/AP_Notify/AP_BoardLED.h b/libraries/AP_Notify/AP_BoardLED.h
index 7de41286ff..a6eaaa1361 100644
--- a/libraries/AP_Notify/AP_BoardLED.h
+++ b/libraries/AP_Notify/AP_BoardLED.h
@@ -26,10 +26,10 @@ class AP_BoardLED: public NotifyDevice
 {
 public:
     // initialise the LED driver
-    bool init(void);
+    bool init(void) override;
 
     // should be called at 50Hz
-    void update(void);
+    void update(void) override;
 
 private:
     // counter incremented at 50Hz
diff --git a/libraries/AP_Notify/AP_BoardLED2.h b/libraries/AP_Notify/AP_BoardLED2.h
index 8b0ab50c7a..06b82238aa 100644
--- a/libraries/AP_Notify/AP_BoardLED2.h
+++ b/libraries/AP_Notify/AP_BoardLED2.h
@@ -28,10 +28,10 @@ class AP_BoardLED2: public NotifyDevice
 {
 public:
     // initialise the LED driver
-    bool init(void);
+    bool init(void) override;
 
     // should be called at 50Hz
-    void update(void);
+    void update(void) override;
 
 private:
     // counter incremented at 50Hz
diff --git a/libraries/AP_Notify/Buzzer.h b/libraries/AP_Notify/Buzzer.h
index 22eb2487cf..1235e8f826 100644
--- a/libraries/AP_Notify/Buzzer.h
+++ b/libraries/AP_Notify/Buzzer.h
@@ -30,10 +30,10 @@ public:
     Buzzer() {}
 
     /// init - initialise the buzzer
-    bool init(void);
+    bool init(void) override;
 
     /// update - updates buzzer according to timed_updated.  Should be called at 50Hz
-    void update();
+    void update() override;
 
     /// on - turns the buzzer on or off
     void on(bool on_off);
diff --git a/libraries/AP_Notify/Display.h b/libraries/AP_Notify/Display.h
index 20856c1206..25369e1c7d 100644
--- a/libraries/AP_Notify/Display.h
+++ b/libraries/AP_Notify/Display.h
@@ -13,8 +13,8 @@ class Display: public NotifyDevice {
 public:
     friend class Display_Backend;
 
-    bool init(void);
-    void update();
+    bool init(void) override;
+    void update() override;
 
 private:
     void draw_char(uint16_t x, uint16_t y, const char c);
diff --git a/libraries/AP_Notify/ExternalLED.h b/libraries/AP_Notify/ExternalLED.h
index 98aee27cc5..e4a301617d 100644
--- a/libraries/AP_Notify/ExternalLED.h
+++ b/libraries/AP_Notify/ExternalLED.h
@@ -31,10 +31,10 @@ public:
     ExternalLED() : _pattern(NONE) {}
 
     // initialise the LED driver
-    bool init(void);
+    bool init(void) override;
 
     // should be called at 50Hz
-    void update(void);
+    void update(void) override;
 
 private:
 
diff --git a/libraries/AP_Notify/RGBLed.h b/libraries/AP_Notify/RGBLed.h
index be35859b3c..ed0bb09fa0 100644
--- a/libraries/AP_Notify/RGBLed.h
+++ b/libraries/AP_Notify/RGBLed.h
@@ -27,14 +27,14 @@ public:
     RGBLed(uint8_t led_off, uint8_t led_bright, uint8_t led_medium, uint8_t led_dim);
 
     // init - initialised the LED
-    virtual bool init(void);
+    virtual bool init(void) override;
 
     // set_rgb - set color as a combination of red, green and blue levels from 0 ~ 15
     virtual void set_rgb(uint8_t red, uint8_t green, uint8_t blue);
 
     // update - updates led according to timed_updated.  Should be
     // called at 50Hz
-    virtual void update();
+    virtual void update() override;
 
     // handle LED control, only used when LED_OVERRIDE=1
     virtual void handle_led_control(mavlink_message_t *msg) override;
diff --git a/libraries/AP_Notify/ToneAlarm.h b/libraries/AP_Notify/ToneAlarm.h
index 58c6d1935a..d5ced3ff45 100644
--- a/libraries/AP_Notify/ToneAlarm.h
+++ b/libraries/AP_Notify/ToneAlarm.h
@@ -30,10 +30,10 @@ public:
     bool init(void) override;
 
     /// update - updates led according to timed_updated.  Should be called at 50Hz
-    void update();
+    void update() override;
 
     // handle a PLAY_TUNE message
-    void handle_play_tune(mavlink_message_t *msg);
+    void handle_play_tune(mavlink_message_t *msg) override;
 
 private:
     /// play_tune - play one of the pre-defined tunes