Backlight Bleeding on DS XL

[magick]

I have some backlight bleeding on my DS XL in the left corner of the bottom lower screen (near power switch) and the right side of the top screen (where I open it). The bleeding showed on the first day but I didn't notice it until night-time as that's the only time you can notice and when there is a black screen. Is this normal on the DS XL and is it caused by pressing the power button and opening the case or should I take it back and swap it for another? I read that someone went through five DS XL before he got one with no bleeding.