I have a question about the way the Raydat declares how many channels it has available when I boot the Apple music app.
It seems it only shows as an 8 channel device with the Stream setting only allowing 8 channels at a time.  So as core audio only sees the raydat as 8 channels it is unable to deliver 5.1 instead of the full 7.1.4
I get around this by using Loopback which shows as a 16 channel device thus allowing Apple Music to deliver 7.1.4.
If I on the fly switch my output back to the raydat it still plays 7.1.4 until I restart the Music app and then it reverts back to 5.1 because the raydat shows as 8 channel device.
I made a video demonstrating the issue
https://youtu.be/mq_gdeeBHuc?t=203