heh – Not caring may be the better choice, but, I’d like to work this out and heaven help us that MS has anything on this (at least as far as I’ve found).
Running Windows 7 Professional, here’s a screen shot of what it looks like on my side. I keep “system sounds” off.
Am I seeing some kind of extreme limiting in streams? Even solo instruments show this on some tracks. Just puzzled about it. 
Thanks for the answer and screenshot.