Everyone thinks Joker is sending him these messages. I think it's Jason Todd himself as the Red Hood. Think about it. Jason defiled the old suit with that message, and Bruce gets a clipping that says "You let your family die." Referencing "Death in the family" where Joker kills Jason. Bruce would have kept the suit and bronzed it to preserve it. Obviously, Jason knew he was Batman since he was once Robin. So he knows how to get at Bruce.