As with Marc Deslauriers, I am also experiencing this problem in Natty (Also in Maverick & Lucid).
Unfortunately, since upgrading to Natty, when it fails to eject, it also fails to complete the burning process. Previously in Maverick/Lucid, it would still have completed the burn, but failed to eject.
Blake commented on using another directory other then /tmp/ which has worked for me, I used /home/$USER and it the burn completed, but failed to eject.
As with Marc Deslauriers, I am also experiencing this problem in Natty (Also in Maverick & Lucid).
Unfortunately, since upgrading to Natty, when it fails to eject, it also fails to complete the burning process. Previously in Maverick/Lucid, it would still have completed the burn, but failed to eject.
Blake commented on using another directory other then /tmp/ which has worked for me, I used /home/$USER and it the burn completed, but failed to eject.