cd/dvd drive wont mount discs

[anivegmin]

cd/dvd drive either fails to mount at all or will mount immediately after system boot then randomly unmount some time afterwards and become unmountable.

Ubuntu 10.04 LTS

# /etc/fstab: static file system information.
#
# Use 'blkid -o value -s UUID' to print the universally unique identifier
# for a device; this may be used with UUID= as a more robust way to name
# devices that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type> <options> <dump> <pass>
proc /proc proc nodev,noexec,nosuid 0 0
# / was on /dev/sda5 during installation
UUID=517097bb-d3b7-44dc-a9a6-7bbac2f166b9 / ext4 errors=remount-ro 0 1
# swap was on /dev/sda6 during installation
UUID=b6d521d0-fb06-4aea-b185-32868d9e57c1 none swap sw 0 0

lrwxrwxrwx 1 root root 3 2010-06-15 10:19 /dev/cdrom -> sr0
lrwxrwxrwx 1 root root 3 2010-06-15 10:19 /dev/cdrw -> sr0
lrwxrwxrwx 1 root root 3 2010-06-15 10:19 /dev/dvd -> sr0

/dev/sr0:

ATAPI CD-ROM, with removable media
 Model Number: TSST CD-RW/DVD-ROM TSH492B
 Serial Number:
 Firmware Revision: TB04
Standards:
 Supported: CD-ROM ATAPI-1 -2 -3
Configuration:
 DRQ response: 50us.
 Packet size: 12 bytes
 cache/buffer size = unknown
Capabilities:
 LBA, IORDY(can be disabled)
 DMA: mdma0 mdma1 mdma2 udma0 udma1 *udma2
      Cycle time: min=120ns recommended=120ns
 PIO: pio0 pio1 pio2 pio3 pio4
      Cycle time: no flow control=240ns IORDY flow control=120ns
Commands/features:
 Enabled Supported:
      PACKET command feature set
      DEVICE_RESET command
    * DOWNLOAD_MICROCODE
      Removable Media Status Notification feature set
HW reset results:
 CBLID- above Vih
 Device num = 0