TL4000 drive showing down in Netbackup

Hi All,

We have been recently seeing an issue with Netbackup dropping a drive as it is running the backups. Opening up IBM's tape diagnostic, it also only shows one drive. If I disable the Qlogic ports in Windows 2003 (64-bit), and then re-enable them, both drives work and everything is ok. The issue will come back anywhere between 1 -4 days and I have to repeat everything again.

In Windows's Event Manager I can see the following error:

The device 'IBM TotalStorage 3573 Tape Library' (SCSI\Changer&Ven_IBM&Prod_3573-TL&Rev_C.00\5&315a2991&0&000001) disappeared from the system without first being prepared for removal.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

The device 'IBM ULT3580-HH5 SCSI Sequential Device' (SCSI\Sequential&Ven_IBM&Prod_ULT3580-HH5&Rev_D2AD\5&315a2991&0&000000) disappeared from the system without first being prepared for removal.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

Does this look like an issue with the Qlogic card, or the drive in the TL4000? The drivers are updated to the latest for the Qlogic card.
Any help would be appreciated.