Running Mandrake90 I had somewhat the same problem when using supermount. I couldn't read all CDs. At least not all the time. Sometimes I could read a particular CD a couple of times and then, all of a sudden -kabanga-, I gor read-errors and could at most get the table-of-contents. Rebooted into Bills OS and all worked perfectly (shudder).
BUT
I have no problems no more though. - Removed/Commented the cdrom/supermount row in fstab and added the old faithful users-doing-it-for-themselves row.
(just a hint, mine looks something like:
/dev/cdrom /mnt/cdrom auto noauto,user,ro,iocharset=iso8859-1,codepage=850,umask=0 0 0)
and now all is well - all the time.
--
OK, it's not exactly the same problem you have - but if supermount can behave strangely in my case maybe, maybe
