Can't blame you for that
The problem I'm experiencing is when I put a DVD in my drive and try to rip it I see the following (number of bytes copies varies):
$ dd if=/dev/sr0 of=dvdcopy.iso
dd: reading ‘/dev/sr0’: Input/output error
1408+0 records in
1408+0 records out
720896 bytes (721 kB) copied, 3.49125 s, 206 kB/s
I can even mount it in Thunar and browse to it, seeing all the files, but I still get the same problem trying to rip it.
However, if I then proceed to open the DVD in VLC or Kaffeine it will almost always rip using dd afterwards.
I'm assuming I just need to do something to ensure the device is ready for reading before I dd but I have no idea what that would be.
Oh, the drive is a Pioneer USB DVD RW/multi recorder but I seem to recall having this problem with IDE drives also.