My rear carpet does not lie smoothly, especially along the hump. When the seat slides back it catches on the carpet. I am interested if anyone else has noticed this problem. I have not yet raised this issue with my dealer but plan to in the near future. My last car was a 2004 G35 coupe and the carpets were much heavier and laid down very nicely along the back floor.

 

I noticed this on mine as well. I re-positioned the carpet under the seat with it moved all the way back (but tilted forward) and it seems to be alright now. I don't move the seat forward and back at all though, so that might make a difference. The carpet just seems to be very stiff and may need some time to conform to the curves of the floor.

You might take a hair-dryer to it with it in place in the car to heat up the rubber backing and allow it to lay in-place. Or wait for summer.

 

On the rear carpet there are black plastic clips that slid under the trim to hold it in place make sure that the clips are all inserted for a flat fit.

 

you could try taking them out and folding them up.. let them sit a while then put them back in