I have one of the new units that came with the red dot fix. I finally checked for the hiss & at 0 volume I can hear a loud hiss from about 3 feet away. I am using Klipsch speakers (ref 20's in front, C7 center & S6 dipole sides) Hiss is coming from it sounds like the tweeter horn, did not take the grill off the mains. Using ATI 1505. Does it sound like I need to exchange mine?? With volume up I can't really hear the hiss.