I'm sorry but IMAO if users doesn't see the problem, then there is no problem. We're not all as sensitive to such things, that's the same for music where people could spend thousands of dollards on an hi-fi system and i won't pick the difference with my Altec speakers.
However I can see it : ) and it's really awfull on certain games (war3) and annoying on desktop. I got the tiny sound too, on certain apps, when I scroll mouse.
My card is the MSI non-Ultra 5900, running on a A7N8X with Athlon XP 2400. I got a 500w Enermax ps. (if nvidia is still collecting data and if this can help)
And I hope it will be soon fixed.