Hi there, I have exactly the same problem as the original post, my Pioneer DVD-121 drive still does this after i updated the firmware, the same happened to my Pioneer DVRA07 after a firmware update, i corrected this by flashing an older firmware back onto the drive, i have not resolved the DVD-121's problem and it's really annoying, i noticed that it tries to install itself twice everytime i boot up and fails on the second attempt because its already installed, try googleing "the firmware page" as a firmware update could fix it. good luck.
James