NEED HELP (please) -- Problem with dark background - ANY icon style

I've been using LO ever since it first came out with StarOffice - and
before that StarOffice, so I've lost track of the years experience, but
I've used it for authoring over 5000 technical reports running 50-1500
pages.  (VERY happily I no longer have that job... :-)  ).   Today I
have LO installed on 4 machines, 3 Linux and 1 Windows, and I use all of
them regularly.  FWIW, I don't think I'm hitting a simple "newbie" error.

So far as I can tell, I have exactly the same settings on ALL 3 of the
Linux boxes (and they're virtually the same on Windows).  (all 3 boxes
have Nvidia graphics cards - and all they share the same
display/keyboard/mouse through a KVM switch).

The problem is that on my primary workstation, the background remains
VERY dark no matter which icon set I'm using (specifically '#33393b'). 
This makes it virtually impossible to use some of the darker icon sets,
and no matter which icon set I try, this dark background leaves many of
the icons nearly "invisible".

I have NO idea what's causing the problem - this machine shows no other
display differences (on ANY application) among any of the Linux boxes.

Has anyone seen this before?  (I have searched through the past 3 years
of emails but I haven't seen any reference to it.)

If not, does anyone have any suggestions to try?  As this is also my
main writing machine this situation makes it much harder to work on
anything, and I've been battling this for about a year now with no
helpful results.

I suspect a corrupted configuration file somewhere but I haven't been
able to find it, and I am the only user on this machine who has the
problem. 

Any advice or suggestions will be (a) tried, and (b) greatly appreciated.

Thanks in advance,

  -- Bill

-- 
william w. austin                                  wwaustin@gmail.com
"life is just another phase i'm going through. this time, anyway ..."