diff --git a/owrx/sdr.py b/owrx/sdr.py
index cad207e..9a177d4 100644
--- a/owrx/sdr.py
+++ b/owrx/sdr.py
@@ -20,7 +20,8 @@ class MappedSdrSources(PropertyDelegator):
     def handleSdrDeviceChange(self, changes):
         for key, value in changes.items():
             if value is PropertyDeleted:
-                del self[key]
+                if key in self:
+                    del self[key]
             else:
                 self._addSource(key, value)