I’ve only had it happen to me once on an S182M. I believe I had just oversped a Verbatim DVD-R (media code MCC 03RG20) 16x to 18x and attempted to scan it. I pressed the eject button, and it sounded as if the drive was only spinning down to 1x (after you have stopped accessing the disk, but haven’t yet ejected it). I pressed the eject button some more to help hurry the process along, and lo and behold, there was a plastic-to-plastic sound and the disc was still spinning. It happened a few days ago, and I only remember because I was worried the drive was going to ruin an otherwise perfect disk. I can’t say for sure that I will have the problem again, but I know it happened that day.
[untested, unproven, and 100% hypthetical theory coming]
My very off-the-wall theory for my situation is that the has a preset time to open the tray, probably taking into account that the optical assembly is at its home position and any disc inside will only take a short amount of time to spin down from that point. I suppose when I pressed the eject button right after I had sent the command to stop scanning, the drive took it’s time to spin down only to a lower speed (possibly as a result of a residual software command), returned the optical assembly to the inner track, and (erroneously) assumed that everything was okay to open the tray as normal.
Also a (more likely) possibility is that, for that isolated incident, the drive’s timing was way off, it wasn’t reading its RPMs correctly (I had just burned at 18x and partially scanned the disc), and it proceeded to eject, thinking that it was safe.
This drive seems to have a pretty rigid and proper setup to eject the disc, by what I can tell from the accoustics the drive produces [I usually hear the disc spin down and the optical assembly seek home]. But maybe (since it has happened), with the combination of environment (system setup–hardware, software, etc), media/media type, and usage patterns, it can occur more than once. Or I could be blowing hot air and it just be one of those random occurances that had no real cause.