[SOLVED] Automount CD or DVD doesn't work (consistently)

Question

Problem with mounting CD's / DVD's and Device Notifier
DVD's are not mounted in /media/, and the Device Notifier does not show them.
CD's (which aren't actually mounted)  I can always access in Dolphin with "AudioCD:/", but Device Notifier rarely pops up (maybe 1 out of 10 times).
facts:
- No device listing in /etc/fstab for DVDROM
- File in /etc/hal/fdi/information/<device>.fdi has bool set to 'true' (and I tried deleting the whole file as well)
- HAL notices that the CD / DVD is inserted (with lshal -m):
storage_model_DVDRW___DVR_K17B property storage.removable.media_available = true
- Tried deleting .KDE4 profile, but that didn't change anything,
- I've got Ubuntu 10.10 installed on the same hardware, and it mounts / shows everything without problems (conclusion: problem is not hardware-related). Ubuntu doesn't use HAL.
- SystemSettings -> Removable Devices -> Automount on Attach is enabled (just in case),
- USB flashdrives and external Hard Disk are mounted and shown by Device Notifier without problem.
- I do get these errors with cat /var/log/errors.log | grep sr0, but they also appear in the rare event when a CD or DVD is actually mounted and shown by Device Notifier:
DVD:
Sep  7 13:55:05 localhost kernel: end_request: I/O error, dev sr0, sector 4096
Sep  7 13:55:05 localhost kernel: Buffer I/O error on device sr0, logical block 1024
Sep  7 13:55:05 localhost kernel: Buffer I/O error on device sr0, logical block 1025
CD: 
Sep  7 13:58:57 localhost kernel: end_request: I/O error, dev sr0, sector 0
Sep  7 13:58:57 localhost kernel: Buffer I/O error on device sr0, logical block 0
Sep  7 13:58:57 localhost kernel: Buffer I/O error on device sr0, logical block 1
(the CD in this case was actually shown by Device Notifier normally! So these errors don't seem to have anything to do with it)
I don't think this is HAL - related, so it must be udev, dbus (not likely), or maybe KDE / device notifier.. ?
How do I troubleshoot this? Any suggestions?
Using:
Linux laptop 2.6.35-ARCH #1 SMP PREEMPT Fri Aug 27 17:14:28 CEST 2010 x86_64 Intel(R) Core(TM)2 Duo CPU T7500 @ 2.20GHz GenuineIntel GNU/Linux
Hal 0.5.14-4
Dbus 1.2.24-1
KDE 4.5.1
Last edited by christopher72 (2010-09-09 22:54:10)

Answer 1

Problem solved:
At one time, I was using the [testing] repo.  Removed it from pacman.conf a week ago, because i wanted to get back to the stable packages.  I re-installed all the older versions of the packages that are in core / extra and that pacman warned me about.  Did not get any further warnings after that, so I assumed everything was fine, and the rest of the system was stable and working just fine.  But something must have been broken, see the above.   In other words: I messed up things without knowing about it. :-S
Today I added [testing] again to check if this would solve my problems, and it did!
Or... is it just the newer version of udev that is in testing at the moment. :-)  Who knows.
This leads me to my next question: how can i safely disable [testing] and return to stable packages, without breaking anything?