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Same thing started to happen to me. Strange thing is that its not constant, sometimes it will happen and sometimes it wont.  In most cases it was when driving at or over 150km/h for me but once it happened at 130km/h while wind was blowing in my direction. 
Seems like something is lose somewhere and strong air resistance starts to make the sound.
I also noticed that it stops if I open driver window a bit and it seems like its coming from the left ( driver ) part of the car.  I tried placing hand on everything in the car to feel if something was vibrating but without luck. 

Hello my friend!!I finally found solution!A Renault mechanic from Greece "Renault  Automotivo" in Leoforos Kifisias Avenue solve the problem.Indeed its from drivers side but he didn't told me the "secret".You can contact if you want with Renault in Greece and i can give you more information 

renault automotivo is the central renault in Greece i think.

Hello again.In Greece Teoren Motors is the central for Renault.You will contact with Mr Stavros Mperdousis-Automotivo-Kifisias Avenue he knows if you explain him that you have an aerodynamic noise.If you want any further information tell me to help you

Do you have any contact info ? I'm not from Greece and  I wasnt able to find hist contact info using google.