switched theme / icons, lost volume control applet icon

[Rick Reynolds <rick rickandviv net>]

I followed the instructions on this tutorial: 
http://www.linuxplanet.com/linuxplanet/tutorials/6223/1/  which shows 
how to configure gnome to look a lot like OSX.  It works very well and 
I'm awfully pleased with it.

However, for some reason when I add the volume control applet to my top 
panel it doesn't show up.  At first I thought some kind of app problem 
was to blame, but when I click around very carefully, I find that the 
applet is actually there and running.  It's icon must be one pixel wide 
and perhaps colored the same as the underlying panel (??).

I'd like to do whatever I need to to override this icon with something 
visible.  Can anyone direct me on where to look to figure out what the 
volume control applet is currently using for its icon?  And then how to 
replace it (I could always just put a different icon file in place, of 
course).

Thanks,
Rick