As is usual, finding something (almost) completely unrelated to what I was Googling. Looks like this is came out a couple years ago, too 
. Anyhow, https://clarimate.us. Review by Bret Pimentel is here.
A very brief summary is that it's a electronic "mute" for your clarinet. You can hear what you're playing, via headphones, but everyone else just hears that your keywork is clicky and you should invest in some key oil.
* Can be a MIDI controller / has MIDI out via USB.
* Software for Android, iOS, macOS, and Windows.
* On sale for $299. Ends July 31, 2024.
* Works with Bb and A clarinets.
* Now supports Bluetooth, but I didn't read the https://clarimate.us website that closely.
. Anyhow, https://clarimate.us. Review by Bret Pimentel is here.A very brief summary is that it's a electronic "mute" for your clarinet. You can hear what you're playing, via headphones, but everyone else just hears that your keywork is clicky and you should invest in some key oil.
* Can be a MIDI controller / has MIDI out via USB.
* Software for Android, iOS, macOS, and Windows.
* On sale for $299. Ends July 31, 2024.
* Works with Bb and A clarinets.
* Now supports Bluetooth, but I didn't read the https://clarimate.us website that closely.
