bizzare - it seems to be rendering the reflection map from the scope's eyepiece over your view, which may explain why it comes and goes - as your view bobs the eyepiece may move enough to snap that out of your vision.
I'd call hax if that reflection actually could show you someone behind you ;)
note that once the ghost image appears, it doesn't change - so if I get some ghost image of a pyro flaming me I'm stuck with that until such time as it magically stops (or I /quit).
I guess it's really just going to be trial and error with the graphics settings in that cfg. Turn one thing back on (to default), see if it fixes it, if not turn it back off and turn something else back on.
I seem to have fixed this issue with -dxlevel 81 in my launch params (then removing it once it's been changed).
The main issue with my fps_config is that water is no longer opaque, meaning if you jump in the water in 2fort I'm coming after you for some no-scope aqua lovin'.
I remember in QWTF when I got my Creative Voodoo 2 8MB and could then see through the water on 2fort5r because of the GL QuakeWorld 3D rendering. Totally rad. :D