diff --git a/js/src/hooks/use-presence-positions.ts b/js/src/hooks/use-presence-positions.ts
index 02cf716..c54a47f 100644
--- a/js/src/hooks/use-presence-positions.ts
+++ b/js/src/hooks/use-presence-positions.ts
@@ -45,6 +45,11 @@ export function usePresencePositions(
       }
     }
 
+    // Sort each segment's presence list by humanId for stable render order
+    for (const presenceList of result.values()) {
+      presenceList.sort((a, b) => a.humanId.localeCompare(b.humanId));
+    }
+
     return result;
   }, [playbackMarkers, children, networkHumans, currentUserId]);
 }