Using the ExpressCard slot for SxS cards (XDCAM-EX) in Mac OS, I noticed that sometimes they dpn’t appear to “seat” properly, removing and reinserting the card normally fixes this. I wondered if it was just my machine, but I just read of a similar experience by others: [http://www.dvinfo.net/forum/sony-xdcam-ex-cinealta/144158-sxs-cards-mount-inconsistently.html].