Correct regarding the level of hissssssssss changing. It remains constant. Been awhile since I played seriously with equipment like this...I fiddled with the system last night and got it sounding pretty good. In a big room, these little system related sounds/noises are not going to be noticable. Like you, I was a bit suprised at the hiss...I believe the Mackies were quieter...perhaps not though. Thanks again Scott...Now where are those snakes....