diff --git a/src/ca/access.cpp b/src/ca/access.cpp
index 14343ed89..8702ed870 100644
--- a/src/ca/access.cpp
+++ b/src/ca/access.cpp
@@ -394,6 +394,9 @@ int epicsShareAPI ca_add_masked_array_event ( chtype type, unsigned long count,
             *monixptr = pSubsr;
         }
     }
+    else {
+        pSubsr->destroy ();
+    }
 
     return status;
 }