What files in the AppData\Roaming\Kodi\ control audio config?

I have a setup at home where i am experimenting with skin customisation, and are syncing the content of AppData\Roaming\Kodi\ via powershell when i am publishing changes to all my boxes.(i have 4 kodi computers).

One of them is attached to a large screen, and has multiple channel sound output. My thinking is that after i publish skin changes etc, i want to reconfig the audio settings just on the one device. I have a script that can do that, what i am not sure about is if i understand what files control audio config.

my belief is that AppData\Roaming\Kodi\userdata\guisettings.xml controls the audio settings of the local system. Does the audio config live in another part of the kodi profile folder – it seems like when i copy this file back on that one host, althought the passthrough settings are respected, theNumber of channels reverts back to 2.0?

Any idea why this would be, and if audio is defined in another file?