Facing same issue here.
Microsoft considers 36kpbs as bit rate the enough to transport voice. They builded the Satin codec to meet their requirement, work ins low band and be able to speech to text in the neural level.
First fact: External systems connection to MS environment, like Cisco, works with other codecs, like Opus, an adaptive and flexible codec. Using Cisco cameras, monitoring the call statistics, we the down bit rate of opus over 60kpbs, and up bit rate, not over 34kpbs. On the same meeting, joining the MS Teams meeting using the Chrome, and opening the chrome://webrtc-internals/, we see the same down and up bit rate, CONCLUDING THE LOW BIT RATE IS NOT CAUSED BY CVI, BUT MICROSOFT. Joining in different meetings, like Webex and Zoom, we don't face the same poor audio than MS Teams. Monitoring the call statistics, the up stream of Webex and Zoom exceeds the 34kpbs of Teams, reaching 60kpbs, 64kpbs in Opus, more information sent to another side.
Second fact: Joining in different meetings, like Webex and Zoom, the audio is better? Yes. We just reach same quality in Teams when we talk very near of the Cisco table microphone. MS Teams probably doesn't have DB gain on audio capture features, once It was designed to be used on PCs, with headsets, and consequently, near of the microphone.
Avoiding a lot of complain about MS Teams, in my perspective, the solution of the poor audio on MS Teams Meetings using CVI, is improve the audio capture using better microphones on the desks, in quality, or quantity.
Docs related:
https://techcommunity.microsoft.com/t5/microsoft-teams-blog/satin-microsoft-s-latest-ai-powered-audio-codec-for-real-time/ba-p/2141382
https://learn.microsoft.com/en-us/microsoftteams/meeting-policies-audio-and-video
https://www.youtube.com/watch?v=p8ml3jYt9KI on 49:50 TT
