Hello... I'm ashame to say that I have been using a cheater plug with one of my amps. I just picked up a Monster HTS-5000, and I wanted to find out why this certain amp kept humming. I have seven amps (5/2-ch,2 mono blocks) that I use in my HT. The amp in question is my Nak PA-7AII. I use two of these for my front/rear spks (passive bi-aming highs/mids). I also use a Nak PA-5AII for my side spks, and two Onkyo M-508 "Grand Integra's for the lows. The amp that hums, uses a power cord that has 3 prongs, and the other two Nak amps uses power cords that has 2 prongs. I switched the power cords and the cord with 2 prongs didn't hum in any amp. I took the power cord with 3 prongs and removed the negative piece as it became a 2 prong plug. I covered the hole with black tape and powered it up. The hum went away. What I'd like to know is my power amp/equitment in any danger with the simple tweek that I did? If this isn't a problem, would it work with powered subs? My Velodyne has a hum, but it goes away with the cheater plug. I called to find out if they made a 2 prong plug, they don't. A lady in customer service told me that it's no problem at all to use a cheater plug. Any facts on this subject? Thanks!!