diff --git a/libraries/AP_HAL_ChibiOS/ToneAlarm.cpp b/libraries/AP_HAL_ChibiOS/ToneAlarm.cpp
index 4b1d02fafc..565fb54bc6 100644
--- a/libraries/AP_HAL_ChibiOS/ToneAlarm.cpp
+++ b/libraries/AP_HAL_ChibiOS/ToneAlarm.cpp
@@ -32,7 +32,10 @@ const char* ToneAlarm::tune[TONE_NUMBER_OF_TUNES] = {
                                 "batt_war_fast:d=4,o=6,b=512:8a,8a,8a,8a,8a,8a,8a,8a,8a,8a,8a,8a,8a,8a,8a,8a,8a",
                                 "GPS_war:d=4,o=6,b=512:a,a,a,1f#",
                                 "Arm_fail:d=4,o=4,b=512:b,a,p",
-                                "para_rel:d=16,o=6,b=512:a,g,a,g,a,g,a,g"};
+                                "para_rel:d=16,o=6,b=512:a,g,a,g,a,g,a,g",
+                                "modechangeloud:d=4,o=6,b=400:8e",
+                                "modechangesoft:d=4,o=6,b=400:8e",
+};
 
 //Tune Repeat true: play rtttl tune in loop, false: play only once
 bool ToneAlarm::tune_repeat[TONE_NUMBER_OF_TUNES] = {false,true,false,false,false,false,true,true,false,false,false};
diff --git a/libraries/AP_HAL_ChibiOS/ToneAlarm.h b/libraries/AP_HAL_ChibiOS/ToneAlarm.h
index ee28b5e9c7..05a110dedd 100644
--- a/libraries/AP_HAL_ChibiOS/ToneAlarm.h
+++ b/libraries/AP_HAL_ChibiOS/ToneAlarm.h
@@ -108,8 +108,10 @@
 #define     TONE_GPS_WARNING_TUNE               8
 #define     TONE_ARMING_FAILURE_TUNE            9
 #define     TONE_PARACHUTE_RELEASE_TUNE         10
+#define     TONE_NOTIFY_MODE_CHANGE_LOUD        11
+#define     TONE_NOTIFY_MODE_CHANGE_SOFT        12
 
-#define TONE_NUMBER_OF_TUNES 11
+#define TONE_NUMBER_OF_TUNES 13
 
 #ifdef HAL_PWM_ALARM