I recently purchased a fan controller for my case fans to reduce the noise when I don't need a lot of cooling power. However, it's actually made it worse. When I decrease the fan speed with the controller, it does reduce the sound of the airflow BUT it increases the sound of the fans themselves. The motors of the fans make a slight growling noise when not running at stock speeds that that actually creates more noise than running the fans at full speed. Anyone have any recommendations?