just received a 7005; never had Marantz before; hooked it all up, including hdmi from directv sat box; and had a horrible ground loop hum; not there when I had Meridian gear and hd621 switch to handle combined ht and two channel..tried to trouble shoot, keep coming back to Marantz piece; they are going to send me replacement; not yet arrived; so I 'm not sure if problem is Marantz 7005 or sat box...but it looks great....
