Problem with the " one page " scroll up / down

Hi,
Once again, i’d like to thank Kriesi’s team for always being so reactive !

I have a little problem, I don’t know if it caused by using Enfold with WP 4.0.
I have created a one page website with parallax effect and when I click on each button in the navigation bar ( linked to each section of the page with links of this type : http://www.mywebsite.com/#section ), it works but the “smooth” scroll down effect is not working : it goes straight to the section as if it was gong to a new page instead of “moving ” down to the section ( if that makes sense ? ).
It was working perfectly with the old version of WP / Enfold.
Is there any solution to fix that ?

Thank you for your help.