LinuxMint13 troubles detecting inserted DVD/CD
 

I have two DVD drives that are giving me trouble in LinuxMint13. Both are older PATA drives that have worked previously, although intermittantly, under Mint.

The one I am debugging right now is a Samsung DVD-ROM ST616T. This one is a reader only, but is better at reading damaged disks than my other drive, a burner, a NEC DVD_RW ND-3540A.

When I insert a commercial DVD video into the Samsung, when it works, here is what I see:

When it doesn't work, which is most of the time, I don't see any output from udisks. The behavior is similar if I try to monitor things with "udevadm monitor --udev" ... If I see output from udisks or udevadm, the disk automounts and plays. If I don't see any output, no automount. And I cannot manually mount it either (as root) with "mount -t iso9660 /dev/sr1 /mnt/tmp". I get the error message "no medium found on /dev/sr1" when trying to manually mount the disk.

This drive used to work well under Mint, so it is possible the hardware is going and the occassional successes I see are just temporary blips where the hardware decides to work. However, I am suspicious of this hardware assumption based on what I see from the other NEC drive. It detects and automounts commercial DVD video disks fine every time. However, it only rarely automounts a DVD that I have burned myself. And I burn them in this same NEC drive (using "growisofs ... -dvd-video ...") that is failing to read it's own burns. In order to read them after burning, I had to use the other (now failing) Samsung drive or my standalone DVD player hooked up to my tv.

One other thing on the Samsung drive. Recently it has started to ignore it's hardware eject button on occassion. Upon testing, I found that the hardware eject button would start working again after a power-down reboot. So my thought was a firmware lock placed by Mint. But then the button stopped working even after a reboot. So I tried "eject -i off" to see if that would clear the firmware lock (which should have been cleared by the reboot, but wasn't). Then after "eject -i off", the Samsung always ejects by either hardware (button) control or by software control ("eject /dev/sr1" and also "eject -t /dev/sr1"). This has got to be some freak thing, because there is no way a firwmare lock should be able to persist across a power-down reboot.

Anyway, that's my story. I'm looking for tips on how to further debug this. I am not certain that there is not some software element at play here. Unfortunately I am fresh out of PATA optical drives to swap out. And those are very hard to find for sale these days. I have ordered a SATA one, and a SATA-to-PATA interface adapter gizmo that attaches to the back of the drive. I am skeptical of that setup, but it was cheap enough that I thought I'd go ahead and try it. $17.99 for a Lite-On SATA DVD burner and $6.99 for the PATA adapter.

It might be the quality of dvds. See k3b output for example.

[SOLVED] LinuxMint13 troubles detecting inserted DVD/CD
 

Apparently my problems were indeed all hardware, and did not have a software component as I initially suspected. I just had two flakey drives.

The new LiteOn SATA burner and the SATA->PATA adapter cured all my problems. LinuxMint recognized it perfectly on powerup. So far, all DVD's I insert - whether commercially made or burned by me - have been recognized and mounted. And the drive responds perfectly to it's hardware eject button and also to software eject commands.

It also rips DVD's several times faster than the old drive did. And it has successfully read problem DVD's that threw my old burner into fits. The one thing I've noted however, is that it doesn't appear to honor my burn speed request ("growisofs -speed=1 ..."). Even when specifying speed=1, growisofs reported it burning at 6x. The old drive burned at 2x when speed=1 was specified, so obviously it is not an exact science trying to set burn speed this way. But as long as I get good burns, I am happy with the higher speed. So far so good. I use Taiyo Yuden 8x blank DVD-R's

Well, I learned something new today. It's probably general knowledge for everybody else for the last few decades, but I just learned it!

CD/DVD burners are not variable and do not burn at any speed up to their max speed, which is what I thought they did. There are discrete burn speed steps that depend on each specific drives capabilities. My new LiteOn burner is able to burn DVD-R's at 6x or 8x only. So when I specified "speed=1", it gave me the closest it could get to 1x, which happened to be 6x for this drive, it's slowest speed.