
I doubt this is a Quadra-specific problem.  I had to get
rid of my "venerable" Bernoulli 20 last year (with enough 
cartridges purchased at ~$90 each to make the whole thing 
worth more than my whole computer ;).  The tech support guys
at Ocean Microsystems suggested that some third-party drivers 
might fix the problem - in my case the cartridges wouldn't 
format/mount/partition for A/UX.  