GET YOUR BEARINGS CHECKED, DONT LISTEN TO ADVICE ABOUT IT BEING TYRES ETC.
My car had done 14k and had a rumbling noise and i didnt pay any attention after reading the post at 16k i asked my friend who used to work in seat to get it checked out he did and it was wheel bearing so they replaced, it is now so quiet.
Way to check is go down long quiet road at say 30-40 and turn hard to right for a few secs then to left, if it stops making noise on either turn it could be bearing on that side otherwise go into empty car park and do a circle in opposite directions.