[Bug]: Disabling an input channel in Audio Settings changes the mapping of track inputs

Detailed steps on how to reproduce the bug

Using DemoRunner and RecordingDemo with the only change that stereo pairing of channels was turned off in examples/common/Utilities.h -> EngineHelpers::showAudioDeviceSettings.

To reproduce:

Start DemoRunner
Open Audio Settings
Assuming you have two or more inputs, disable the first input channel.
Plug your mic / audio device into channel two.
Open "Audio Recording" demo.
Create a single track (clear tracks first).
Check the 2nd input channel on the track.
Record

The recording will be silent, however if I change track input to channel 1 I get a signal, even though mic is plugged into channel 2. This indicates that the track inputs no longer map to the correct input channel.

What is the expected behaviour?

Track inputs should map to the device input channel of the same name since the track inputs list the same names as the physical device inputs like "Input 5", "ADAT 7", "SPDIF 2".

Unit test to reproduce the error?

No response

Operating systems

Windows

What versions of the operating systems?

Windows 10 Pro 21H2

Architectures

x86_64

Stacktrace

No response

Plug-in formats (if applicable)

Standalone

Plug-in host applications (DAWs) (if applicable)

No response

Testing on the `develop` branch

The bug is present on the develop branch

Code of Conduct

[X] I agree to follow the Code of Conduct

Tracktion / tracktion_engine