subform displays no records when its recordsource is a query

I have a subform based on a query; for simplicity the query is just
SELECT * FROM [MyTable]. When I test this subform standalone (i.e. not
nested in the parent form where it will eventually need to go), it
correctly queries the underlying table and I'm able to navigate to all
the records in that table.

Problem: when I drop this subform into it's parent form, it doesn't
show any records! I've disabled all the master/child filtering options
on the subform control, but it doesn't seem to make a difference. The
subform shows no records.

Here's the kicker: when I change the subform's recordsource to
[MyTable] (instead of a query based on [MyTable]), everything works
correctly and I see all the records (even when it's nested in the
master form). Seems like a bug; thoughts?