Sordina
The short answer: Teams only lets you change its speaker volume during a meeting. In the meeting, open More (…) › Audio settings and set the speaker volume there.
Teams' own volume
- Join or start a meeting.
- Click More (…) in the meeting controls, then Audio settings.
- Choose your speaker and set its volume.
Outside a meeting, Settings and more › Settings › Devices lets you choose the speaker, but has no volume slider.
Other audio settings
- Noise suppression filters background noise from your microphone. It doesn't change how loud others sound to you.
- Spatial audio spreads voices around you on supported headphones.
With Sordina
Sordina puts a slider for every app that's playing in your Mac's menu bar, so you can set Teams against everything else in one place. That part is free.
- Click the Sordina icon in the menu bar.
- Drag Teams's slider, or click its mute button.
- Everything else stays where it was. Teams keeps its level until you change it.
Unlike Teams' own control, the slider is there outside meetings too.
Music down during meetings
Sordina Pro's Calls turns other apps down while any app uses the microphone, Teams included, and brings them back after. See how to turn down music automatically during calls.
Common questions
Why can't I find the volume in Teams?
It only appears during a meeting. Join one, then open More (…) › Audio settings.
Teams is quiet but everything else is fine
Check Teams' volume in a meeting's Audio settings, and that it's using the speaker you expect.