usually i have it so icons will invert as needed, but i've been having trouble seeing the audio and wifi icons in my system tray. just in case, i set it to "always" to invert them, and even that didn't work.
screenshot w/ my OS & build:

EDIT: turns out it's because of "use software rendering" setting being checked... but something else to note is "when needed by theme" is set, it doesn't invert the icons for System XP.