Hi there, welcome to the forum.
Given the date you mentioned, I suspect it could be this issue (but I don’t use obs studio and your error message could be different).
You’ll see there it was due to a change in
which was updated on the 05-mar.
It serms to have already been fixed upstream, and also obs made an adjustment, but you’ll have to wait for the next release of the obs package. Or you could downgrade v4l2loopback-dkms in case of urgency.
-—
Edit:
Reading back both your logs and the story of that issue i’m more convinced it’s something different.
But I would anyway try a downgrade v4l2loopback-dkms due to the date of last release.