Mac hangs when MS Bookshelf 94 CD inserted

[Cliff Hathaway <cliff@CS.ARIZONA.EDU>]

We've got a Mac LC520 running MacOS 7.1 and At Ease 1.0, with 8MB of RAM.
The builtin CD drive is a 2x model, and works fine on the other CDROMs
that we have for the students (Encarta, Groliers, etc).  About half the
time when we insert the Microsoft Bookshelf 94 CD, the system hangs.  When
we reboot it, it reports that the disk is unreadable.  We can't get this
to fail on either of our newer Performas.

This is the only machine we have that uses the CD caddies, (which we think
is a good idea, as the students aren't always as careful as they should be
when they remove the disks), so we'd like to be able to continue to use
Bookshelf on this machine.

Has anyone had similar problems?  Suggestions?

TIA!

Cliff Hathaway
St. Cyril School (K-8)
Tucson, AZ