How do I get two PS4 controllers to work with RetroArch?

Hey there,

I’m almost done with my emulator machine but I’m stuck! I need to get 2 PS4 controllers to work with retroarch. I tried DS4Windows and that works great with other emulators such as PJ64, MESS and Dolphin, but for some reason RetroArch just doesn’t recognise the controllers.

Any help would be appreciated, maybe there’s a config or setting I’m missing.

Thanks

edit: Forgot to mention, I’m on Windows 7, running the nightly build from the 24th of July.