I did some experiments too.

I think that I also remembered that SH and Will noticed the converse: that when they increased cal or trim settings, that the hiss got worse.

For me? Nada. No diff. I tried bumping up all my settings by 4 dB. No change that I could tell.

Then I just played with the rear center, the worst channel I have for hiss. I tried -15 dB and then +10 dB. No change! I was kind of surprised.

Then for kicks, I tried muting the 950. The hiss was still there. I thought jeez, has the problem all along been with my amp/speaker combination? But then I tried 2 things that originally convinced me where the problem was. I turned the 950 off, leaving my amps on, and the hiss disappeared. Then I turned the 950 back on, and no hiss. I only get hiss after a live source has played. (After the 950 leave "global" mute mode.)

I think I have convinced myself that in my system, there's an interaction somewhere between the 950 and my amps, or between the 950 and my speakers, or between the 950 and the particular speakers *and* amps I have. But remember, I did not have this problem with the Sony TA-E9000ES I had in my system before the 950. Luckily, Outlaw is continuing to work on the problem.