Jaz 2GB SCSI

I cannot get a 2GB SCSI Jaz drive to work. I used to have
an external, started having trouble, and so switched to
an internal, and am having the same trouble: I cannot
make backups to the drive. It reads and writes just fine,
all kinds of files, even up to 700 MB at a time, but if I
try to perform a backup program with proprietary software
or MS backup, it hangs every time with Event ID 9 or
others. (not 11) Anyone know anything about Jaz 2 GB
drives I should know?