[Linux V4L] Video isn't working We couldn't use your webcam for video.

I cannot get my video4linux devices working with Teams.

OS: Ubuntu 18.04

When I run Teams it shows a report that all devices are connected:

But then when I do the test call, a message appears on the top:

Video isn't working We couldn't use your webcam for video.

All other V4L-compatible apps like for example Vokoscreen work perfectly.

Any ideas what's wrong with another MS product on Linux?

UPDATE. I checked out logs but found there nother about video or Teams having any issues with video. Basically, when another V4L device gets created, Teams shows no video at all, including the one from the default web camera.