Now it is making sense. I now have 2 Hitachi/IBM drives in my system. The original one is in a "Silent Drive" black box so I can't hear what it's doing. Just about 1 week ago I added an IBM but this IBM is installed in a external case w/ USB connection. It must be the culprit. I confirmed this by turning off the external HD and walla! the ghost is gone!

You guys have successfully exorcised my Plextor and revealed the real ghost, IBM!

Thanks for the help