I also have the same "problem"
My almost new Ultraplex 40 does take a long time to recognize te cd-roms burned by my plex48x
When I test the cd in CD-speed (or Plextools) i get a lot of errors
and, yes it is high quality media, Fuji Film 52x certified.
When I test the same cd in the writer, no errors at all
And if i write the cd
s at 16x speed, the ultaplex doesnt have any problems reading the media at all
So, is the problem in the Ultraplex or is it in the PlexWriter 48x?
I have tried older and newer firmwares for both the Ultraplex and the Plex 48x, but it didn`t matter at all
Maybe Plextor should investigate this?