I think the format of the record is described in AV1 Codec ISO Media File Format Binding, section 2.3 AV1 Codec Configuration Box (https://aomediacodec.github.io/av1-isobmff/#av1codecconfigurationbox-section) though I'm only going to verify if I actually can force it to work.

that link to release notes explains what to do: issue sudo killall coreaudiod, the entire coreaudiod daemon will be killed and a new instance automatically launched. I'm super curious why this is more secure than the old method but there is no any known answer to me yet.

I found the thread, checked and it does work for me (Sonoma 14.1), thought it requires an application bundle id. It doesn't want to accept a VST3 plug-in bundle id nor an XPC service bundle id.