Slow startup of GLVisual on Windows

Hi,
I have a problem using the FXGLVisual. If I enforce GPU rendering in my 
nvidia settings the creation of my GL window takes up to 7 seconds.
If I disable it, the startup is much faster (0.15 seconds) but I get 
only half the frame rate in rendering. I checked with the debugger and 
the time seems to be spent in FXGLVisual::create. I am using Fox 1.6.58. 
It might be a driver problem because I don't remember this for earlier 
versions but it happens on several machines and unfortunately 
downgrading all of them is not a real option.

Is this a known problem and can I do something about it?

Thanks for your help
Michael