RETROARCH crashes with d3d11 and 12 from ver. 1.9.9 on.

I run Retroarch on a system powered by an i7 4790K, outputing 15 khz signal through a R9 380x with CRT Emudriver 2.0 installed.
The machine runs Windows 10 ver. 1511, since it's the Win 10 build with the lowest input latency ever released.
But things gone pretty bad when Retroarch started to crash with d3d11 and 12 drivers, from ver. 1.9.9 onward.
Now we hit RA ver 1.10.3 and it still works only with d3d10 and OpenGL, both delivering lower performance in many cases.
I suspect the changes made to the d3d11 and 12 drivers to accomodate/implement FSR features are causing these incompatibilities with certain systems on which RA worked perfectly before.
Is there something I can do to fix this unexpected driver incompatibility, or I will be forced to upgrade my perfect and stable installation to say, 1903, in order to enjoy new BIG features as Automatic Frame Delay, despite the fact I don't care at all with FSR and the like?
Thanks a lot.

Reproduce the crash on Windows 10 version 1511 with the d3d11 and d3d12 drivers, then compare behavior between RetroArch 1.9.8 and 1.9.9, where the report says the regression began. Review the changes associated with FSR support and confirm that the result works without reducing the available driver options.