No. They sent me out a swap unit to see if the 2 I had were defective but all three performed the same. I get considerable noise out to a foot away from the speaker. I have owned and tested many power amps over the years and none had anywhere near this level of noise. I believe that a decent power amp should add no audible noise to my system. And it is not my system since the noise is the same whether my preamp is connected or not or on mute.I get the noise with no input connection, just a speaker and power. It is not a hum problem as it is wide band "white" noise. I am returning the units for a refund. All 5 channels of my 755 are dead quiet under exactly the smame set up. The M-Blocks in my opinion do not belong in a quality system. I can't imagine having 7 M-Blocks all hissing away in my otherwise quiet listening room. Should have started with the 770.Thanks for asking.