Audio 5.1 surround sound down-mixed to stereo on Mac / OS

Hi,

I have a 5.1 surround sound mix working correctly on Windows. It's set up like this:

6 Audio sources
6 Audio Clips - Each clip is a .wav with 6 channels and audio only on one channel. The other 5 are silent.
1 Audio listener

On Windows, each AudioSource plays audio on one channel -- (i.g. AudioSource1 plays sound only on channel 1, AudioSource 5 only on channel 5, etc.)

But ! On mac, the identical setup plays the same .wav files downmixed to stereo (i.g. AudioSource1 plays sounds on channel 1, AudioSource 6 plays audio on channel 2)

The project audio settings are set to 5.1 Surround. The behaviour seems the same for all build targets.

Details: Unity 2018.3.5f1

Thanks.

 

Update: Even though I was using Soundflower 64 set to 5.1 Surround, I needed to restart Unity to get it to pickup the system output config. The Unity audio mixer is now showing the correct channel output.

Does anyone know if Unity defaults to stereo for iOS deployment ? Seems like Wwise does: https://www.audiokinetic.com/library/2017.1.9_6501/?source=SDK&id=audio__output__platform.html

 

I know that Unity will change the AudioSpeakerMode based on the actual driver capabilites of the sound deice it's playing through.

So if your sound device is only set to Stereo then Unity will ignore your "5.1 Surround" setting in project settings and everything will be Stereo.