Tarmac - ravelling in hot weather

We recently had our drive tarmacced and we are very happy with the job. However, I have noticed that it is starting to ravel where the cars are turning in front of the house. This only appears to be happening during the hot weather.

Should I be concerned ? Will it get worse ?
What can be done about it ?

All advice appreciated

This thread might be worth a read and as it mentions therein you may get some help on www.pavingexpert.com