diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py
index 37a9ef0edb4..8eeab7948af 100644
--- a/synapse/handlers/sync.py
+++ b/synapse/handlers/sync.py
@@ -1534,7 +1534,7 @@ async def _log_client_state_desync(
             )
             if state_error:
                 client_state_desync_logger.warning(
-                    "client state discrepancy in room %s: %s",
+                    "client state discrepancy in incremental sync in room %s: %s",
                     room_id,
                     state_error,
                 )
@@ -1572,7 +1572,7 @@ async def event_id_to_membership(event_id: Optional[str]) -> Optional[str]:
             if event_type != EventTypes.Member:
                 continue
 
-            if state_key not in client_calculated_state:
+            if (event_type, state_key) not in client_calculated_state:
                 error_map[state_key] = ClientCalculatedMembershipStateErrorEntry(
                     actual=await event_id_to_membership(actual_event_id),
                     calculated=None,