The Windows volume sliders don't affect Leitner headsets. Why?

Lately we’ve noticed that Leitners do not work with Windows volume controls. This is both the basic volume slider that left-clicking the speaker icon would bring up, and the sliders in the Levels section of the sound settings. It looks like this is the fault of a Windows update. Bummer. Here is all the chisme:

1) Windows updates so that it is now looking for a code from USB devices from the USB Association. And yeah, that’s a real thing. https://www.usb.org/

2) IPN chose not to join the organization, so Leitner headsets were not issued a code from them.

3) No code = Windows ignoring the headset’s request to use the volume settings. Whoa.

IPN may eventually join this exclusive club, but for now this is what we have.