Hi, Im thinking maybe its the same problem i had with the disk not spinning up in time to be recognised.
It stumped me for quite a while.
They would appear in toolbox but then dissappear elsewhere.
Apparently 3.1 roms fix this but if no 3.1 roms are available then cutting pin 1 of the ribbon cable stops the hard disk being reset thus enabling it to be spinning in time for the next soft boot.
I didn't actually cut my pin 1, i undid the plastic connector and peeled pin one back so it wasnt connected. This way i can recconect pin 1 if i need to.
See ya.