Cracks in Arc housing

Last week i've noticed some cracks in the housing of my Arc I did no drop it or anything and i keep it in a hardened leather case when i'm not using it.

The cracks apear arround the black sensor at the left to the ear speaker(is this the light sensor?) and arround the volume buttons on the right.

I've did some searching on the net and found a few other people on the dutch GOT forum with the same cracks on the Arc. Anyone on XDA got these problems?

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