*snip*

Thanks to everyone who replied! Well, a while after sending the mail I
found the model number faintly written on the back of the drive and after
browsing HP's website for a while I found some information on the
dipswitch settings.

So, as Kevin suggested, I dug out the screwdriver and opened it up. And I
am sure you can guess the picture, yup, it was set with hardware
compression on and no host control. So I flipped it to default off with
host control on and ran tapetype again and got a lot better numbers this
time.

Conny