diff --git a/libraries/AP_Mount/AP_Mount_SToRM32.cpp b/libraries/AP_Mount/AP_Mount_SToRM32.cpp
index 0733c0f1b8..03775f9cdc 100644
--- a/libraries/AP_Mount/AP_Mount_SToRM32.cpp
+++ b/libraries/AP_Mount/AP_Mount_SToRM32.cpp
@@ -136,7 +136,10 @@ void AP_Mount_SToRM32::find_gimbal()
         return;
     }
 
-    if (GCS_MAVLINK::find_by_mavtype(MAV_TYPE_GIMBAL, _sysid, _compid, _chan)) {
+    // we expect that instance 0 has compid = MAV_COMP_ID_GIMBAL, instance 1 has compid = MAV_COMP_ID_GIMBAL2, etc
+    uint8_t compid = (_instance == 0) ? MAV_COMP_ID_GIMBAL : MAV_COMP_ID_GIMBAL2 + (_instance - 1);
+    if (GCS_MAVLINK::find_by_mavtype_and_compid(MAV_TYPE_GIMBAL, compid, _sysid, _chan)) {
+        _compid = compid;
         _initialised = true;
     }
 }