Just noticed that the latest Realtek HD Audio driver R2.82 which seems to be included with the 1903 Windows 10 release preview removes the option to re-assign jacks (rear and front) to different sources such as front output. A bit annoying if you dont have a surround system and use other jacks for other speakers and assign them to front speaker output. Hope they put this right in the next driver version. R2.80 is ok as it still has Realtek Control Panel but this is gone in R2.82.