HP STORAGEWORKS SSL1016 - Manual (Page 64)

Tape Cartridge Usage
64 SSL1016 Tape Autoloader Reference Guide
4. If you hear anything on DLT or SDLT cartridges, do not use the cartridge.
a. If it doesn't rattle, check the tape leader inside the cartridge. To do this,
open the door on the rear of the cartridge by releasing the door lock.
Figure 46: Opening the cartridge door