I just finished a show where we shot 720/24pN onto (2) 8GB cards, offloading to an external 1394 HDD through a PB G4 using P2 Genie.

We are now importing into FCS 5.1.2 from the card files and I'm getting errors on several cards. I am able to play back the clips in FCP's import window, but the audio is very choppy, and at the very end of each clip I get grey artifacting/block-up across the screen. When I try to import, FCP crashes and I have to force quit. I can drag single clips into the queue, but I get the red error icon with "unknown error" on mouse-over.

Initially I thought it was a problem with one of the cards, but I am able to import footage shot on both cards. 4 of the 8 reels we shot are having the above error, and there is no real pattern to the errors (as in-- reels 1-3, 5, and 8 import fine, but reels 4, 6, and 7 have the error).
I'm pretty sure the problem has to do with something not related to the camera and cards because I was able to import the last day's footage directly from the camera without issue.

-We used only one card at a time and used the same slot each time.
-I have not experienced this problem before. Ever.
-Yes, I have the P2 driver installed
-Running OS 10.4.8 on a 2Ghz G5

Any ideas about how to proceed from here?
Much appreciated,