diff --git a/src/tracker/api/tasks.py b/src/tracker/api/tasks.py
index 1c321c5..f0f3630 100644
--- a/src/tracker/api/tasks.py
+++ b/src/tracker/api/tasks.py
@@ -130,7 +130,7 @@ async def _system_message(
 
     await db.flush()
 
-    # Build MessageOut for task comment broadcast
+    # Build MessageOut for task comment broadcast (use broadcast_message, not broadcast_task_event)
     task_msg_out = MessageOut(
         id=str(task_msg.id),
         task_id=str(task.id),
@@ -142,7 +142,10 @@ async def _system_message(
         attachments=[],
         created_at=task_msg.created_at.isoformat() if task_msg.created_at else datetime.datetime.now(datetime.timezone.utc).isoformat(),
     )
-    await manager.broadcast_task_event(str(task.project_id), WSEventType.MESSAGE_NEW, task_msg_out.model_dump())
+    await manager.broadcast_all(
+        {"type": WSEventType.MESSAGE_NEW, "data": task_msg_out.model_dump()},
+        exclude_slug="system",
+    )
 
     # Broadcast chat message
     if chat_msg and chat_id: