I just noticed a regression with openSUSE 12.3. It appears that I can no longer hot-swap the removable media bay device in my computer and expect whatever I place in it to work. It used to be I could swap between the floppy, DVD-RW or second battery device without problems. I only noticed this as an issue when I went from using my secondary battery to the DVD-RW and it would not register, I could not kick open the tray with
umount: /var/run/media/wolfnf/UDF Volume: umount failed: Operation not permitted
eject: unmount of `/dev/sr0' failed
I may try the new kernel, just to try it but I think I have found some kind of solution. I, just for kicks, thought I would add my the groups “cdrom” and “floppy” to my user ID and it looks like it is working normally again. I have removed and re-inserted the DVD-RW several times and it is seemingly working just fine. I did have to eject the disc if I left the disc in the drive when inserting it but other than that, it is working tip-top.
So it seems we come up assigned to no groups and I routinely make these choices though I have not tracked down the problem they cause. We heard that not being a member of the video group can cause problems with the nVIDIA video driver. You might look to see if a bug report on groups not being set extends past the missing video group.