aha!
if you go to device manager, right click on the driver, select properties, and then select the properties tab there is an option to disable the mixer for each device. this appears to have stopped all windows fuckery and given me a clean stream through directsound. it has the strange effect of no longer launching sndvol32, and claiming i have no audio devices installed when i launch mmsys.cpl. but, that's a minor annoyance if it's giving me a clean stream. and, it's actually also uninstalled the wdm device from the device manager altogether.
i've got it set up to play through asio now, and i don't see any value in disabling it. but, it's useful to have the reference of checking to see what it sounds like through a clean directsound out.
i vaguely recall doing this, and vaguely recalling undoing it to access the midi out on the soundblaster. it's the only thing i've done so far that seems to actually turn off the windows interference.