Seagate STD6401Lw

Hi
I was able to get a used external Seagate 4mm tape drive (STD6401LW)
and I would appreciate some help with the configuration. I purchased
a used AHA 2940UW to work with the drive. The tape does back up, but
very slow and many soft write errors. Can one of you please tell me
the correct settings that I should use on the 2940UW and any other
info that will make the drive work better? The last backup that was
attempted indicated that it would take over 5 hours to back up 13 Gb
? The drive makes many ?clicking? sounds when backing up (perhaps
the head seeking ???) I have used a cleaning cartridge on the drive
and using new 4mm media

Thanks for your help
Bill

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