im using the Aya desktop theme which looks grey by default, but an interesting thing is when i go to "aplication appearance" > colors i add the color scheme "tea sun", which is dark scheme. unlike some of the other desktop themes Aya actually changes with the color scheme. it looks pretty sweet, imho. the color changes to a black theme with bronze highlights in widgets even in the clock in the tray with tea sun added.
anyway, unchecking shadows didnt work. but the effect seems to apply to icons i have added to desktop, and not to the default icons that are there from install. ive been a bit busy so i didnt have a chance to search it further yet.
EDIT*** in playing with it more i have come to realize, that it is the color scheme combined with the desktop theme that is causing this on my added icons. in changing either desktop theme or system color scheme makes it go back to normal. also changing the color scheme in the details tab of desktop theme also can change it. but i cant find a a setting for the icon name yet.
edit 2** it seems only when i use the color scheme Tea Sun. all other i dont have this problem. but in none of the setting for can i find how to change it. . . not a major issue, i can use another dark color scheme and edit the colors i like, i just bugs me i cant find a setting,