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Good old FM radio (in stereo) is a 192kHz mux, annoyingly.

That's may be how the back-end of a modern broadcast FM radio transmitter works, but the good old stereo radio transmission itself still the same as it's been for many decades: It is analog, and mid-side encoded, and it remains completely compatible with monophonic receiver implementations.

How so?

Stereo pair, pilot, RDS (the scrolling artist/song text), and the 67 kHz SCA. It's not quite 192kHz as I recall, but that's nearest fit really. AES192/192kHz MPX composite on the back end of every exciter/transmitter when I was last near them.

That's for the FM baseband signal, not the audio. Among other things you're doing here, you're basically treating a stereo signal (plus a pilot that effectively contains no information, plus an extremely low bitrate RDS stream in an extremely inefficient way) as one monaural signal.

But maybe there's a use case for replacing an AES192 signal carrying the full FM baseband signal over ETH-67? I'm not sure it's the correct fit, though.

That's how radio works now, it's owned by like 3 companies. Automation/playout for large groups of stations is all centralized, and they carry the baseband over IP to transmitter. Radio solved it awhile ago.

https://www.telosalliance.com/radio-processing/audio-interfa... etc.

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