I've got one, and it did a great job at eliminating the hum coming from my amp's chassis. NOT hum from speakers, which speak to other issues in your system. I'm a big fan. Both it and CI's solution have 30 day trials I believe, which is great just in case the DC isn't the problem. Also means you have a decent chance of getting one B-stock from them or someplace else with a 30 day guarantee like Music Direct.