The 9500 has separate internal ('fast') and external ('slow') SCSI controllers and buses. Is it possible that you (even unwittingly) changed termination or ID on the LaCie drive after successful use of it? Is it a d2 CD-ROM? Whether or no, check that the term on slide-switch is depressed if the LaCie is the last or only device in the external chain, and raised if the LaCie is not last. SCSI ID=3 for CD-ROMs in most later Macs, and that keeps it away from HDDs at ID=0, 1 or 2.
As a potential clincher that the drive is still A1, how does it behave with, say, the Colour Classic and HFS-formatted CDs? Another consideration is that Mac OS X CDs are formatted HFS+, as befits the New World order, and your existing CD-ROM driver may know nowt about such new-fangled stuff, regardless of what OS 9 knows. Continuing that line, what does the Beige G3 do with an HFS or HFS+ CD in the LaCie? LaCie provided Silverlining as an alternative to HD SC Setup or Drive Setup, the version depending on the OS/System on the Mac. With OS 9, LaCie 6.5.1 would be appropriate if you can lay hands on it, and offers a far more informative and supportive setup for HDDs and optical drives (whether SCSI, USB or FireWire).
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As a potential clincher that the drive is still A1, how does it behave with, say, the Colour Classic and HFS-formatted CDs? Another consideration is that Mac OS X CDs are formatted HFS+, as befits the New World order, and your existing CD-ROM driver may know nowt about such new-fangled stuff, regardless of what OS 9 knows. Continuing that line, what does the Beige G3 do with an HFS or HFS+ CD in the LaCie? LaCie provided Silverlining as an alternative to HD SC Setup or Drive Setup, the version depending on the OS/System on the Mac. With OS 9, LaCie 6.5.1 would be appropriate if you can lay hands on it, and offers a far more informative and supportive setup for HDDs and optical drives (whether SCSI, USB or FireWire).
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