Hi, I bought the Kobo Aura 4 days ago and I'm really happy with (as I already read 3 books with it

). There's just this one thing: when I put on the frontlight there is a dark band at the top and the bottom of the screen (see pictures). I don't know if everyone has these bands. If so, I can live with it and hope the manufacturers can perfect this technology. If this is a production fault however, I'd like to know if I should return this unit and ask for a new one.
Note: I saw a thread about someone having the same issue with the Kobo GLO. As the Aura is a newer model I thought maybe Kobo sorted this issue out.