When Constituent Record Security is enabled, users can no longer get results on certain membership queries. The problem is with the OOB function UFN_CONSTITID_MAPFROM_REVENUETRANSACTIONID which relies on the notorious "backwards compatible" REVENUE view. The REVENUE view does not contain financial transactions of type Membership Installment Plan.
We're currently evaluating this issue for a fix in a future release.
Steps to Duplicate
Query on revenue with constituent record security enabled