diff --git a/ArduSub/GCS_Mavlink.cpp b/ArduSub/GCS_Mavlink.cpp
index a281cec56b..abca6bd455 100644
--- a/ArduSub/GCS_Mavlink.cpp
+++ b/ArduSub/GCS_Mavlink.cpp
@@ -945,7 +945,9 @@ void GCS_MAVLINK_Sub::handleMessage(mavlink_message_t* msg)
         mavlink_set_home_position_t packet;
         mavlink_msg_set_home_position_decode(msg, &packet);
         if ((packet.latitude == 0) && (packet.longitude == 0) && (packet.altitude == 0)) {
-            sub.set_home_to_current_location(true);
+            if (!sub.set_home_to_current_location(true)) {
+                // ignore this failure
+            }
         } else {
             // sanity check location
             if (!check_latlng(packet.latitude, packet.longitude)) {
@@ -958,7 +960,9 @@ void GCS_MAVLINK_Sub::handleMessage(mavlink_message_t* msg)
             if (sub.far_from_EKF_origin(new_home_loc)) {
                 break;
             }
-            sub.set_home(new_home_loc, true);
+            if (!sub.set_home(new_home_loc, true)) {
+                // silently ignored
+            }
         }
         break;
     }
diff --git a/ArduSub/GCS_Mavlink.h b/ArduSub/GCS_Mavlink.h
index cb88c49b96..ef6ca90e8c 100644
--- a/ArduSub/GCS_Mavlink.h
+++ b/ArduSub/GCS_Mavlink.h
@@ -32,8 +32,8 @@ protected:
 
     bool vehicle_initialised() const override;
 
-    bool set_home_to_current_location(bool lock) override;
-    bool set_home(const Location& loc, bool lock) override;
+    bool set_home_to_current_location(bool lock) override WARN_IF_UNUSED;
+    bool set_home(const Location& loc, bool lock) override WARN_IF_UNUSED;
 
 private:
 
diff --git a/ArduSub/Sub.h b/ArduSub/Sub.h
index 04a78a5bee..8a5f0d4182 100644
--- a/ArduSub/Sub.h
+++ b/ArduSub/Sub.h
@@ -507,8 +507,8 @@ private:
     void userhook_SuperSlowLoop();
     void update_home_from_EKF();
     void set_home_to_current_location_inflight();
-    bool set_home_to_current_location(bool lock);
-    bool set_home(const Location& loc, bool lock);
+    bool set_home_to_current_location(bool lock) WARN_IF_UNUSED;
+    bool set_home(const Location& loc, bool lock) WARN_IF_UNUSED;
     bool far_from_EKF_origin(const Location& loc);
     void exit_mission();
     bool verify_loiter_unlimited();
diff --git a/ArduSub/commands.cpp b/ArduSub/commands.cpp
index f11fc36760..f77af7ba51 100644
--- a/ArduSub/commands.cpp
+++ b/ArduSub/commands.cpp
@@ -13,7 +13,9 @@ void Sub::update_home_from_EKF()
         set_home_to_current_location_inflight();
     } else {
         // move home to current ekf location (this will set home_state to HOME_SET)
-        set_home_to_current_location(false);
+        if (!set_home_to_current_location(false)) {
+            // ignore this failure
+        }
     }
 }
 
@@ -25,7 +27,9 @@ void Sub::set_home_to_current_location_inflight()
     if (inertial_nav.get_location(temp_loc)) {
         const struct Location &ekf_origin = inertial_nav.get_origin();
         temp_loc.alt = ekf_origin.alt;
-        set_home(temp_loc, false);
+        if (!set_home(temp_loc, false)) {
+            // ignore this failure
+        }
     }
 }
 
@@ -65,7 +69,9 @@ bool Sub::set_home(const Location& loc, bool lock)
     const bool home_was_set = ahrs.home_is_set();
 
     // set ahrs home (used for RTL)
-    ahrs.set_home(loc);
+    if (!ahrs.set_home(loc)) {
+        return false;
+    }
 
     // init inav and compass declination
     if (!home_was_set) {
diff --git a/ArduSub/commands_logic.cpp b/ArduSub/commands_logic.cpp
index a7b18d84f0..44218fd18b 100644
--- a/ArduSub/commands_logic.cpp
+++ b/ArduSub/commands_logic.cpp
@@ -765,10 +765,14 @@ void Sub::do_change_speed(const AP_Mission::Mission_Command& cmd)
 void Sub::do_set_home(const AP_Mission::Mission_Command& cmd)
 {
     if (cmd.p1 == 1 || (cmd.content.location.lat == 0 && cmd.content.location.lng == 0 && cmd.content.location.alt == 0)) {
-        set_home_to_current_location(false);
+        if (!set_home_to_current_location(false)) {
+            // silently ignore this failure
+        }
     } else {
         if (!far_from_EKF_origin(cmd.content.location)) {
-            set_home(cmd.content.location, false);
+            if (!set_home(cmd.content.location, false)) {
+                // silently ignore this failure
+            }
         }
     }
 }
diff --git a/ArduSub/motors.cpp b/ArduSub/motors.cpp
index 459f760b14..8086c4c67f 100644
--- a/ArduSub/motors.cpp
+++ b/ArduSub/motors.cpp
@@ -52,7 +52,9 @@ bool Sub::init_arm_motors(AP_Arming::ArmingMethod method)
         // Log_Write_Event(DATA_EKF_ALT_RESET);
     } else if (ahrs.home_is_set() && !ahrs.home_is_locked()) {
         // Reset home position if it has already been set before (but not locked)
-        set_home_to_current_location(false);
+        if (!set_home_to_current_location(false)) {
+            // ignore this failure
+        }
     }
 	
     // enable gps velocity based centrefugal force compensation