Allan,
        We have an STK9714 with DLT7000 hooked up to an IBM RS6000 under
AIX.  We had the problems that Kelly was talking about (and more) with the
library.  After weeks of trouble shooting and parts swapping, the cause
turned out to be the cable going from the SCSI card in the CPU to the
robot.  

We also had a bad drive that was causing read errors on the tapes.

Check the activity log ("q ac" command) and see if you can track the error
to a specific drive.  Since the error is on the changer, and you don't see
any tapes left in the drive, it probably won't be a bad drive.  Also, since
the error is SCSI related I'd bet on the cables being bad.  Have your
service tech. run a new set of cables to the library.  Just run'em accross
the floor temporarily.  And see if you get through a day without the error.
 At the same time you're doing that, you may want to have your NT server
tech check the SCSI card, to be sure that isn't the problem.

Brad Wallace
UNIX Systems Administrator
The Guardian Life Insurance Co.