Audacity cannot record in stereo Mac OS

First, check that Audacity has permission to access the “microphone”: see this post.

Next, go to Apple (menu) > System Preferences > Sound > Input. Do you see “USB Audio CODEC” there? If not, you need to find out why. If the Mac cannot see the interface neither will Audacity. If it is there, select it.

Start Audacity and look at the Device Toolbar. Can you select USB Audio CODEC as the Recording Device? If so, can you then choose “2 (stereo)” in the Recording Channels dropdown menu?

– Bill