Well - I had a dreaded hum that I temporarily fix with a 2 prong (3 to 2)..but although it eliminated it - its not the way to go in fixing the hum - dangerous I hear...Most of us know that a ground loop hum comes from - at most times - your cable line...sure enough for me it was. What I did was add a cable ground block radio shack and then took a ground wire (I had an old lamp lying around that had a ground wire that I removed), then I put the ground on the block and then unscrewed a little my wall outlet (that is grounded) and wrapped the ground around the screw and tighten it up - and now the HUM is completely gone..I read this somewhere by some guy at AVS..