diff --git a/owrx/source/sdrplay.py b/owrx/source/sdrplay.py
index da2398a..5fb2f4c 100644
--- a/owrx/source/sdrplay.py
+++ b/owrx/source/sdrplay.py
@@ -10,6 +10,7 @@ class SdrplaySource(SoapyConnectorSource):
                 "rf_notch": "rfnotch_ctrl",
                 "dab_notch": "dabnotch_ctrl",
                 "if_mode": "if_mode",
+                "external_reference": "extref_ctrl",
             }
         )
         return mappings