I then disconnected/reconnected the headphones, and then relaunched each application one at a time checking the connected codec (hold Option when clicking on Bluetooth menu in toolbar, and navigate to the device). (Skype, Skype for Business, iTunes, Spotify, WebEx Meetings, etc). I exited all applications that might use audio. well this is now completely within the Apple universe. I noticed this same behavior today with my AirPods. This seems to solve the problem, however, it seems annoying that I have to do this every time the headphones connect. I started searching for a solution to this a few weeks ago, and found people disabling the default audio input from their bluetooth headphones to another device, as their headphones were connecting using SCO codec instead of AAC. How did I figure this out? If you have a pair of quality bluetooth headphones (I recently got a Bose QC 35 II), I started noticing a sharp difference in the quality when connected to my iPhone vs my Mac. So what's going on here? Why does Cisco need a hot mic ALL THE TIME? However as soon as I launch the Cisco WebEx Meetings application it immediately captures the active audio input/output and downgrades to SCO despite no active meeting. While trying to debug this I've noticed that if I exit the Cisco WebEx Meetings app, everything goes back to AAC or Not Active. Ever since I upgraded to Mojave, I've noticed that when the app is running any of my connected bluetooth audio devices (AirPods, Bose QC 35 II's) that have microphones get forced into using SCO codec as opposed to 'Not Active' if no audio input/output is needed or AAC which is what you'd expect to see if playing audio such as from iTunes or Spotify. I use the Cisco WebEx Meetings application on macOS daily. Since Cisco support seems to be quiet on this subject, I'll warn other here.

Cisco webex teams mac