How to catch audio device directly on macOS?

Application Development
1

I’m trying to play multi-channel audio with gstreamer on macOS but osxaudiosink plugin doesn’t support up to 9 channels.

I’m using MOTU 24Ao that has 24 outputs, but gstreamer doesn’t recognize all channels.

% gst-device-monitor1.0 Audio/Sink
----
Device found:

	name  : 24Ao
	class : Audio/Sink
	caps  : audio/x-raw, format=F32LE, layout=interleaved, rate=48000, channels=8, channel-mask=0x000000000c00003f
	        audio/x-raw, format={ (string)F64LE, (string)F64BE, (string)F32LE, (string)F32BE, (string)S32LE, (string)S32BE, (string)U32LE, (string)U32BE, (string)S24_32LE, (string)S24_32BE, (string)U24_32LE, (string)U24_32BE, (string)S24LE, (string)S24BE, (string)U24LE, (string)U24BE, (string)S20LE, (string)S20BE, (string)U20LE, (string)U20BE, (string)S18LE, (string)S18BE, (string)U18LE, (string)U18BE, (string)S16LE, (string)S16BE, (string)U16LE, (string)U16BE, (string)S8, (string)U8 }, layout=interleaved, rate=[ 1, 2147483647 ], channels=8, channel-mask=0x000000000c00003f
	gst-launch-1.0 ... ! osxaudiosink device=95

So, I send audio test signal to osxaudiosink, some output don’t play any sound at all.
If I want to use all device channels, is there any option I can use?

(From some other audio software (for example Reaper), I can see all 24Ao channels. So there’s some way using all channels with this mac and audio device.)

environment
macOS Monterey 12.7.6
gstreamer 1.24.6