My grass texture details slide on the terrain

So I've been searching the forums and the internet because it looks like a common problem, but i didn't found anything. It looks like a common known problem with detail meshes that they need to be vertex painted in order to be affected by the wind correctly. In my case it's happening with the grass texture detail, no the detail mesh so i don't know what is causing this. Here's a short video of the problem:

If someone knows something about this please help!!

 

The best you can do in your case ( because it looks strange ) is to try with an older version of Unity and if it works there just fire a bug report because currently it's really hard to get attention and obviously the whole terrain based stuff is broken ! I am also having a ton of issues with terrains...