Summary reports linking to incorrect reports

[dsdart]

In the past, the Membership Report (Summary) has had links from the months that it is grouped by to the detail report for that month.  However, now they link to the Membership Report (Expired). 

Another report that we have created based on Contribution Summary Report to show only new members has the links from the months go to Contribution Detail Report but it no longer honors the group (the person who usually runs these reports swears it did a few days ago).

It looks like the wrong report instance number is being found in the code.  I have cleared the caches and removed the contents of template_c directory.  I don't see this behavior on the demo site. 

Is this 2 separate behaviors or related?  I don't know where else to look to find the fix, so any ideas anybody can give me would be appreciated.

[dsdart]

Reposting in the hopes that someone might have an idea.