Frozen cameras

[jmcns]

I'm looking for general direction here; I can provide much more info as helpful.

Had OBS pre-30 (sorry, I've lost track of the version) which worked wonderfully. Have two cameras - they're identical model/make, and they USB to the computer. Then I updated operating system (Debian, to trixie), and with it came OBS 31. Only one of two cameras now works; other one shows up frozen on very first frame (when adding source afresh), and never moves from that still frame in any context. Basically, I can add EITHER of the two; if first, from scratch, it will work, but the second one will be a frozen image.

I understand that this is commonly considered an (nvidia?) driver problem, but cheese and other apps will show both cameras just fine, so it seems to be an OBS issue. I have tried both OBS 30 and 31 (both via debian, from the main apt source (30) and the multimedia apt source (31), as well as the official flatpak (latest 31)). I also took a fresh machine, installed debian from scratch, then installed 30 and 31 again and both still freeze this way. I have NOT yet tried pre-30, as it's not easy to install on Debian trixie and I haven't gone to the effort of back-versioning a scratch Debian in order to try a pre-30... but I'm guessing I'll have success again when I achieve a setup similar to what I had before my Debian upgrade (and, thus, upgrade of OBS to 30/31).

Any guidance on approach very welcome. Thank you!

 

[Tuna]

Check the selected format of these cams. If you have a format which require higher bandwidth you may exceed the max USB bandwidth for two cams at once.

 

[jmcns]

Thank you for the help. Remember, these very two cameras worked flawlessly on this same computer for almost two years. Now they essentially don't work at all together. No settings changed until I went and, indeed, knocked the fps down to 30 and the resolution down to "tolerable"... just in case. But it doesn't make a difference.

 

[jmcns]

Ok, I discovered at least a workaround. Perhaps this will be useful to others who may have this problem. If, within OBS, when setting up the source (V4L2 Video Capture Device), you explicitly SET the resolution and framerate to what you want (I matched my cameras' output for both), RATHER than leaving them both as "default", then everything works! But, if you leave those untouched when setting up the source, then only one camera will "work" - the other will constantly show a still shot of the first frame upon load. (In my case.)

I've tested this with two different installs with both a version 30 (debian trixie packaged version) and a 31 (deb-multimedia's variant); the result is the same. I did NOT test this with the flatpak, which had lots of other problems and was a very slow startup time, so I abandoned testing with it.