Bug#998718: Brasero fails (on Testing) burning an ISO image on a CD-RW

[Thomas Schmitt]

Hi,

the drive and Brasero work with DVD+RW, unformatted DVD-RW, and
formatted DVD-RW.
No bad symptoms to see, except that i get molested by the automounter
and that i often have to repeatedly double click the drive field and
the "Burn" button before burning begins.

These successes give me the idea that the culprit is some software which
wants to play the CD as audio CD. This needs a different SCSI command for
reading. It's name is READ CD and it can be told to require CD-DA sectors
of 2352 bytes rather than the 2048 bytes of data CD sectors.
This would somehow explain the SCSI error "unaligned write", which then
actually would rather mean "unaligned read".
(This imposes the riddle why the TSSTcorp drive in the USB box does not
cause such an SCSI error message.)

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Tests made:

First i put the DVD+RW into the ASUS and start Brasero. The DVD gets found
and after a few double clicks on the drive field, the Burn button finally
works and "Burning" begins. "Finalizing", "SUCCESS", "Checksum",
loud reading, "Ejecting medium".
No SCSI error.
xorriso -toc shows the written session.
  dd if=/dev/sr0 bs=2048 count=193536 | md5sum
yields the correct MD5.
(That @#$%^ automounter mounted it without asking me. Some other software
pops up the window offering to start the file manager.)

Next try: Brasero starts up with empty tray. Then i put in the DVD+RW from
which i removed the ISO 9660 superblock by xorriso -blank.
All works fine. No SCSI error message.

Now with unformatted DVD-RW, fast blanked by
  xorriso -outdev /dev/sr0 -blank deformat_quickest
This yields a medium state that is only suitable for write type DAO,
which can only take a single session. The DVD-RW is an old 2x speed type.
Full blanking would last about 40 minutes.
Starting Brasero while the DVD is in the ASUS drive.
All is well. Just half as fast as with the DVD+RW.

Now after formatting the DVD-RW by unmounting (grrrr) and this run:
  xorriso -outdev /dev/sr0 -format as_needed
which lasts 40 minutes, i can burn and the drive stays usable.

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Have a nice day :)

Thomas