Issues with 5.1 Surround Sound with Windows 10

run mmsys.cpl

but beware of Skype and other apps that don't comply with the Windows sound APIs. Dr. Lewis

In the last 20 years, Microsoft only paid for Dolby during 2009-2012 in Windows 7.

Microsoft didn't pay for Dolby in Windows XP, Windows Vista, Windows 8, Windows 8.1 and Windows 10.

So, it is not Microsoft that deserves the "blame". It is consumers who forgot that they indirectly paid for Dolby when they bought a DVD burner (which came bundled with windvd and dolby) during the XP era, skipped Vista, upgrade to 7 (and enjoyed the Dolby freebie from Microsoft), skipped 8/8.1, then entirely forgot that Dolby was a freebie Windows 7 exception when they upgrade to Windows 10.

run mmsys.cpl

but beware of Skype and other apps that don't comply with the Windows sound APIs. Dr. Lewis

Skype complies with telephony specifications and uses an ultra-low bitrate audio codec that is specifically designed for telephony. Skype is not supposed to comply to hi-fi audio stuff.

https://docs.microsoft.com/en-us/skypeforbusiness/plan-your-deployment/network-requirements/network-requirements

Well, at last some actual information about Skype's "failures".

I am expressing an opinion when I say that Skype fails completely to deliver audio when the host computer OS (Windows) is set to output 5.1 sound and that an app like Skype that absolutely depends on the best audio possible under the circumstances need not fail in such circumstances.

Your reply explains why the Dr. killed the patient but does nothing to justify the act. We do agree that Skype audio fails in 5.1 mode.

Skype, on loading, could check the environmental sound settings and issue an error message if it discovers an environment known to cause audio failures. This would be the least demanding task for a motivated programmer.

Or, Skype could engage an audio transform "app" that bridged the well-known gap between telephony analog "bit rates" and the demands of 5.1 surround sound. Some sounds get through accurately so the transformation may not be complicated.

How about a script that switches Windows to and from Stereo <-> 5.1 Surround that runs when Skype is loaded and gracefully terminated? Just a couple of mouse clicks for me to do that.

There is nothing to fix. There is no failure on Microsoft's part.

Your issue comes from the fact that if you are using skype and speakers --- skype has to cancel your voice with Acoustic Echo Cancellation so that you don't get massive feedback.

Acoustic Echo Cancellation only works in stereo.

Even if you go and buy yourself a fancy soundcard (instead of using built-in Realtek onboard audio chip) and you use that fancy soundcard's AEC function --- that fancy soundcard's AEC also only works in stereo.