Ebtech's Hum X Ground Loop Exterm. Do they work?

Has anyone ever tried one these ground loop eliminator's from Ebtech. It is the Hum X Ground Loop Exterminator. I am having grounging issues from my cable tv but, when i disconnect cable it is reduced but still their. I was thinking of trying one these on my Plinius intergrated amp. When i turn the volume up, the hum gets louder. Any suggestions is much appreciated.

Thanks
Brian