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NEC 3550, growisofs, -speed and low read speed


I've got a bizarre one for you. I'm running growisofs 6.1 on my
Linux box. I recently got a brand new NEC 3550 DVD burner and ran into
an issue with it. The problem happens the same way with the stock original
v1.05 NEC firmware or the hacked 1Y6 RPC1 variant from Liggy and Dee

If I burn a DVD using growisofs' -speed option:

growisofs -speed=4 -dvd-compat -Z /dev/dvd=dvd.img

then subsequent DVD *reads* will happen at that speed! Needless to say,
this really slows down my md5sum verifications. To verify a 4.5GB
DVD's md5sum takes:

15 min if the previous burn was at 4x
10 min if the previous burn was at 8x
 5 min if I did not specify a burn speed before

The respective loudness of the DVD motor does correspond with the above.

If I power down and restart the system, then I get full speed reads
again until I burn again with growisofs using -speed.

I know that the current write speed set by growisofs is stored in
the unit - but my unit seems to be using this as a max read speed.
If nobody has seen this before, I'm guessing "you will be" ;)

At first I thought it might be riplock, but this drive is not
riplocked. In any case, it happens even with non-video data DVDs.

I think that growisofs should leave the drive as it found it before
growisofs was called (regardless of whether an error occurred or not).
At the very least, I seem to need a utility to be able to reset the
drive speed back to its default so that I will not have to reboot
to do my md5sums ;)

I didn't try it with cdrecord, so I do not know if that is likewise

  Thanks in advance for any help or advice,

  Mike Shell

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