I have a powered subwoofer that has 60 hz transformer hum. This hum occurs simply by plugging it into an outlet and not having the interconnect attached. The transformer is firmly seated and the power cord is two prong. I took it apart yesterday and separated the components. When I took the transformer out of the enclosure, thus separating it from the driver, the hum went away. Two questions: Any ideas on how to shield the transformer from the driver magnets (the driver has a bucking magnet for shielding)? How would I go about replacing the transformer?