This bug has two parts to it that are both related to switching audio devices

Note: it requires a computer setup with 7.1 and Stereo audio devices (device emulation should work too, though it was not tested)

Steps for issue 1:
1. Open user-submitted project
2. Load Scene "scene"
3. Select GameObject in the Hierarchy and make sure Speaker Script 1 is the only script enabled on it
4. Make sure the default audio device in Windows is 7.1
5. Enter Play Mode
6. Look at the Console - it reports the active audio device to be 7.1
7. Disable the default device (7.1) while still in Play mode. Windows/Unity will switch to the Stereo device
8. The following warning appears: "Default audio device was changed, but the audio system failed to initialize it. Attempting to reset sound system."

Steps for issue 2:
1. Repeat steps 1-4
2. Disable the 7.1 device while keeping it the default one, Windows will switch to the Stereo device
3. Enter Play mode
4. Console and Mixer should report that the current audio device is Stereo
5. Enable the 7.1 device, making Windows and Unity switch to it (while still in Play mode)
6. Console is still reporting the audio device as Stereo
7. Disable the 7.1 device, making Windows and Unity switch to the Stereo device
8. Check the console to see it now displaying 7.1 as the audio device

Expected result: switching audio devices should not end up in odd warnings or wrongly detected devices
Actual result: Unity throws a warning when downgrading the number of channels and fails to properly detect the device

Reproduced with: 2017.1.1f1, 2018.2.0f2, 2018.3.0a7