Well I figured out my first problem - the apparent drop in loudness after the inital calibration. That darn Rat Shack meter eats batteries pretty good. Seriously, once I put in a new 9V, the measured loudness went back up. So another calibration (00 volume, 75 dB) and my settings are back in the -8 to -11 range.

The hiss and hum is definitely volume related and only are significant at a volume of 00 and higher. Yes there are lots of reason for hum in a system, but nothing changed in my system except the blue dot. My old unit hisses, but never really hums and again, this is a constant at ALL volume settings. For the blue dot, is this a problem in practice? I am still not sure. Because of this I recalibrated at -10 volume (still 75db), hoping this would keep me further away from the nasties. Then again, I (obviously) had to up the trims, so maybe it is a total wash. I will keep experimenting and let you know. I do know that with it cal'd at 00/75, I was able to clip my amps with the volume set at 00 during the opening of Toy Story 2 (when the words Toy Story 2 come flying forward). So it seems like there is enough gain - or I need a bigger amp

Finally, the clicking mute circuit is definitely annoying. Any totally quiet part of a DVD (like the FBI warning or a silent menu) and I hear it. Pause the DVD and click. Rewind the DVD for more than a second and click. I can handle it during the speaker cailbration, where each channel change makes a click, but during the movie - uggh.

I think the unit is quiet enough to not even need the mute circuit. I guess they wanted to be sure it wouldn't hiss when just sitting there (set on a digital input anyway). I wish they hadn't gone that far. I guess I have a few more days to decide what to do....