It's been working flawlessly since the fall of 2017 feature update with the built-in usb audio 2.0 Win driver.
I reluctantly installed the latest driver from Music Tribe and now JRiver sees it as a 4 channel device, but Windows sees two two-channel devices, 1-2 and 3-4. It's OK for now but not ideal, MC runs great. I also did a support ticket with MT. Using this with a file server-turned-htpc for my lanai, so no surround for Netflix as of yet.... I tried the WDM but it was way out of sync and I didn't want to deal with that. I hope other usb dacs are being affected similarly with 1903, then there's a better chance of MS correcting it at some point.
I can't uninstall feature update 1903, or count on this being corrected any time soon by MS. If I don't find a solution soon another OS install may be in order.