Cactus Data Shield - Different drives see different sessions

Hello everybody,

I have bought a package with two protected audio CDs. I have checked them in two drives (located in different computers) and each drive sees something else in the case of one of the CDs. Do you have an idea why?

Drive 1: DVD writer (NEC 6500A)
Drive 2: DVD-ROM (HL-DT-ST GDR8162B)

On drive 1, running “Search for bad sectors” in ClonyXXL returns an error message on both CDs. On drive 2, this operation runs without problems on both discs.

The pink CD can be successfully ripped on both drives in EAC. (And the rips are identical if you rip this CD several times on the same drive). ISO Buster sees the same thing on both drives: one audio session and one data session. ClonyXXL detects this CD as Cactus Data Shield on both drives.

The black CD generates read errors and sync errors in EAC on both drives. (And the rips are different if you rip this CD several times on the same drive). On drive 1, ISO Buster sees only one session containing 18 audio tracks and ClonyXXL sees it as an unprotected audio CD. On drive 2, ISO Buster sees two sessions (the first containing 18 audio tracks, the second 1 data track) and ClonyXXL sees it as a Cactus Data Shield protected CD.

Both computers run WinXP Home Edition SP2, ASPI 4.60, EAC 0.95pb3 (set up to use ASPI), ClonyXXL, ISO Buster 1.7 (freeware version, set up to use SPTI).

Do you have an idea what is going on with the black CD? Why does it show up differently on the two drives?

And why is the copy protection not effective on the pink CD?

Thank you in advance,