Could you describe your hardware *exactly*?  What brand motherboard,
disks, disk controller?  I *know* there are IDE drives with buggy
firmware that will cause random reordering of data, that manage to get
to market because they seem to work with DOS just fine.  (Maybe you
already did and I missed it; I tend to not pay much attention to the
mailing lists these days.)

For the record, I've never seen problems with `doreallocblks' or
`doasyncfree' on any machines I have, but it was suggested to me a
while back by Kirk that there `might' be a problem with that code.
I've never heard any more about it from him, and I *have* asked.