I am in no way trying to diminish the performance of the VTF-3 sub. It is a GREAT product! That said, I have received numerous emails regarding the POPPING nuisance that the VTF-3 amp exhibits. My VTF3's are working....or sounding just fine...its just that household appliance noise that exists in the AC line causes the subs to "burp and pop." If I turn on the ceiling fan...the subs will pop. If my wife turns on her hair dryer...I can hear a pop...if I turn off the power to the sub (switch on back of unit) it will pop. I can actually get the subs to come out of their "sleep/standby mode" by turning on the ceiling fan and rotating the speed selector switch...that is just goofy! HSU says that this is not a problem, won't hurt the sub, and is normal because of the sensitivity of the amp. The thing Is I have had several SVS, M&K, Velodyne subs hooked into the exact AC circuit that did not exhibit this problem. I believe this is a design problem with the VTF-3 amp and to date I am not aware that Dr. HSU has even acknowledged that a problem exists? I have received numerous letters from HSU customers who have fixed "THE PROBLEM" ...message below: Mike, I have experienced the same noise on turn off if the led was green. One problem is caused by arcing as the power switch opens. You can resolve it completely by putting a . 01 kV disc cap across each leg of the power switch. This will suppress the spark! I also suggest a . 01 kV disc cap across the AC mains input. This helps to keep line interference from entering the amplifier. I have done 3 things to my VTF-3 amplifier to eliminate line noise pops: (1) I floated the ground on the amplifier chassis and plugged the cord directly into the power source. (2) I verified that the absolute phase was wrong and corrected the polarity of the AC mains input wiring. (3) I also installed the . 01 disc cap across the mains input. This cleared up popping noises I would get when other appliances were switched on or off. >>>>>>>>>>>>>>>>>>>>>>>>>>>> WHAT IS THE DEAL HERE?????? We just have to live with this...because.....ahhhh...it's inherent in the design sensitivity of the amp??? Seriously...is that the only answer? Mike Sloan "A satisfied HSU customer "