I had my Lumia since launch (yellow) and it built up a nasty bit of dust, anyway I dropped that phone numerous time and it stayed true to the known Nokia name....until it fell on the volume rocker, which still worked but was difficult to use. Att sent me a refurb replacement and it IS brand new, I've had it for about a week now, and the camera lens has ZERO dust under it! Could it be that att sends it to Nokia to fix the dust? because from what I understand it that ALL Lumia 920 have this problem due to a design issue