Not sure what the sound issue is, but in FC3, the static /dev directory has been replaced by its
dynamic counterpart /udev, Great!!! :-). FC2 supports both /udev and /dev. I've been using udev in
FC2 to control mapping a particular USB drive/camera to a particular /udev device. Anyone
who has multiple usb flash storage devices, and that connects/disconnects them in no particular
order, /udev is a great solution.
Not yet upgraded to FC3 myself, but have been reading the release notes.
They can be found here:
Be sure and check out the udev section.
Oh and regarding FC3, it appears that udev needs to be upgraded after FC3 is installed. More on that here:
Back to your /dev/cdrom problem, check the /var/log/message logs and see what /udev/... device
got mapped to your cdrom.