Re: LaCie drive going down!

This may not help, but it's close enough to your problem to suggest it. I just had problems with
a 4 drive ATA RAID, where I was getting the same problems as you're describing. Tech Tool Pro
said the drives were fine (using the drive's SMART function). I was able to rebuild the directory
for the RAID with Disk Warrior, but I was still getting errors, and when I opened the RAID onto the
desktop it would say there were tons of files in the folder, but they wouldn't show up. All the files on the RAID
were video so I did a Find, looking for Type/Movies. I was able to copy all the files from the Find window
to another RAID. I did a surface scan of the individual RAID drives and it turned out that one drive had over 500 bad
blocks. I erased all the drives and wrote zeros to them (which can fix bad blocks), re-striped them and they're working fine now.
Have you tried Disk Warrior to rebuild the directory? Have you used Tech Tool or Disk Utility to check
the drives?
Ed