MS4200RS changing the display color ?

Yesterday I've got my new MS4200RS that I bought on eBay.
To my surprise the background color/light on the display is white. I'm a bit surprised by this since I have only seen pictures of these units whit blue background light in the display. Is there some option in the menu (that I have overseen) to change the color ? Or must i replace the front or change the led ?

The MS4200RS is not designed to change the background illumination color. I suppose, this set has a hardware modification or is a development sample.