[AccessD] Date field sort

I have an odd problem with a report that sorts on a date field.

3 times now for no reason I can discern the sorting gets strange.  The first
time it happened, I used Cdate([MyDateField]) and it started sorting
correctly again.  Then I had to take the Cdate() off, then put it on again.
Only one or the other works, but they alternate.  

The wrong sorts will sort like a string.  Months are grouped together
regardless of year and december comes before January.  And yes, I have had
it sort like a string when I used Cdate().  

Has anyone seen anything like this in the past?

Debbie
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