diff --git a/pype/ftrack/events/event_sync_to_avalon.py b/pype/ftrack/events/event_sync_to_avalon.py
index 31387b5934..2fcaf01f69 100644
--- a/pype/ftrack/events/event_sync_to_avalon.py
+++ b/pype/ftrack/events/event_sync_to_avalon.py
@@ -1731,13 +1731,20 @@ class SyncToAvalonEvent(BaseEvent):
         attributes_joined = ", ".join([
             "\"{}\"".format(name) for name in hier_cust_attrs_keys
         ])
-        [values] = self.process_session._call([{
+
+        queries = [{
             "action": "query",
             "expression": (
                 "select value, entity_id from CustomAttributeValue "
                 "where entity_id in ({}) and configuration.key in ({})"
             ).format(entity_ids_joined, attributes_joined)
-        }])
+        }]
+        if not missing_defaults:
+            if hasattr(session, "call"):
+                [values] = session.call(queries)
+            else:
+                [values] = session._call(queries)
+
         ftrack_project_id = self.cur_project["id"]
 
         for attr in hier_attrs:
diff --git a/pype/ftrack/lib/avalon_sync.py b/pype/ftrack/lib/avalon_sync.py
index 88013a55b4..61a916a70e 100644
--- a/pype/ftrack/lib/avalon_sync.py
+++ b/pype/ftrack/lib/avalon_sync.py
@@ -780,10 +780,10 @@ class SyncEntitiesFactory:
                 entity_ids_joined, attributes_joined
             )
         }]
-        if hasattr(self.session, "_call"):
-            [values] = self.session._call(call_expr)
-        else:
+        if hasattr(self.session, "call"):
             [values] = self.session.call(call_expr)
+        else:
+            [values] = self.session._call(call_expr)
 
         for value in values["data"]:
             entity_id = value["entity_id"]
@@ -843,10 +843,10 @@ class SyncEntitiesFactory:
                 "where entity_id in ({}) and configuration.key in ({})"
             ).format(entity_ids_joined, attributes_joined)
         }]
-        if hasattr(self.session, "_call"):
-            [values] = self.session._call(call_expr)
-        else:
+        if hasattr(self.session, "call"):
             [values] = self.session.call(call_expr)
+        else:
+            [values] = self.session._call(call_expr)
 
         avalon_hier = []
         for value in values["data"]: