Re: CLOSE SESSION failed with SK=5h/INVALID FIELD IN CDB: not harmless?
> So it certainly sees /some/ of the UDF info. Gack!
It would be quite some strange incident if a
zeroed block at a more or less random address
would make this all a valid empty UDF filesystem.
I am not sure whether the empty mount directory
is really caused by the altered block(s).
Maybe there is more than one problem at work
> FWIW the drive is connected via USB:
This is sometimes a reason for poor write
performance. But 0.7x effective speed is normal
for "2x" BD media if Defect Management is
USB is not generally known to alter data during
transmission. So for now i would rather suspect
the drive's firmware.
If other BD media show silent alterations too,
then make tests with an USB memory stick on the
same USB socket.
(Again: It would be interesting to learn whether
there are more zeroed blocks on the media.)
Have a nice day :)