Small vibrations in the steering wheel
 

I have a Sonata from 2006. New tyres both summer and winter and yes i have balanced them, twice.
I have been to the garage and done all the service and so on.
They have replaced some parts and also re-balanced the whole front, so now you can not see any vibrations at all on the steering wheel.
BUT after driving for 30 minutes you feel in your fingers the same thing like after using a heavy vibrationg tool, the fingers are getting numb.
What could it be? After talking to the same garage 3 times i now switched to a new one, but they do not find anything.

If no solution, then i must sell the car and buy another but i really do not want to do this.

Please help me with tips, what could it be, what can be done, any in Europe one could ask these questions ???

Thanks / Henrik