I guess I found the problem (high level) and the workaround.
I do use Chromium browser, and it looks like teams fails to "detect" my audio/video devices if the Chromium browser is running BEFORE teams was started or after my system is waking up from a standby. So if I kill/close the browser and restart teams the devices are detected as expected. Launching Chromium after teams is running works fine.
This is no real solution as I have to kill -9 (to be able to restore all tabs on restart) Chromium which I use heavily at work.
Could anybody from Microsoft please let the teams developers know about this finding? It should be easy to fix?