Control: tags -1 + moreinfo Hi Ralf,
On Mon, Dec 01, 2025 at 10:34:52AM +0100, Ralf Jung wrote: > Package: src:linux > Version: 6.17.8-1 > Severity: normal > X-Debbugs-Cc: [email protected] > User: [email protected] > Usertags: amd64 > > Dear Maintainer, > > Since a recent kernel update, my webcam stopped working properly. The webcam > model is "Logitech C920 HD Pro" (USB ID 046d:0892); I will put the full lsusb > output below. What happens is that, when I am in a Zoom call, after someone > else > joins the call, flickering artifacts start to appear: the bottom half of the > image turns gray. I will attach an image. I have so far not been able to > reproduce this outside of Zoom. I tried Jitsi in the browser and Gnome Cheese. > (Zoom does *something* with the webcam when someone joins the call: the exact > frame of the webcam, i.e. how much of the room I see and where the image cuts > off, changes. I have no idea what that is about.) > > I tried playing around with power_line_frequency; that did not help at all. > > This only started recently. I tried booting a 6.12 kernel (with the same > userspace), that fixed the issue -- so it very much looks like a kernel issue > to > me. The issue is also present in 6.16, so it's a regression introduced some > time > between 6.12 and 6.16. I use Zoom fairly regularly professionally, so this bug > means I am pretty much stuck with a 6.12 kernel for now. If you reliably can reproduce the issue then (although I realize that each testing step is time consuming), I would suggest to start a bisect. First though narrow down more closely the Debian versions which expose the problen and not (using the images fetched from https://snapshot.debian.org/). Once you have two upstream versions close enough, start a bisect. Do you need instructions/help on how to do that? Regards, Salvatore
