I heard this noise as well and it's associated with the tranny. It's definitely coming while I am in first gear and while letting out the clutch. I have the 6MT but I also heard this sound while testing the DCT.
It's a "clank-clank" kind of sound as if a few parts came loose under the car. It doesn't happen all the time and I sure hope it's normal or else we got a major recall coming.
DEFINITELY KEEP US POSTED!!!