I'm on a Mac osx 10.14.2
audacity 2.3.0
installed ATR2100-USB, is recognized on the Mac, but does not show up in Audacity.
Closed audacity and relaunched with mic plugged in, still nothing.
Next?
new AT microphone not recognized
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This forum is for Audacity on macOS 10.4 and later.Please state which version of macOS you are using,
and the exact three-section version number of Audacity from "Audacity menu > About Audacity".
Audacity 1.2.x and 1.3.x are obsolete and no longer supported. If you still have those versions, please upgrade at https://www.audacityteam.org/download/.
The old forums for those versions are now closed, but you can still read the archives of the 1.2.x and 1.3.x forums.
Re: new AT microphone not recognized
Thank you. Yes, audacity was already checked. Tried again this morning, and now the mic is recognized. I had read that audacity doesn't always recognize the mic right away. Guess it had to sleep overnight 
Re: new AT microphone not recognized
I suspect the problem was that Audacity was already running when you plugged in the mic. When adding a new audio device (such as the USB microphone), you should do that before you start Audacity.
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