Repeated (unnecessary) "Change in Record Selection Formula" prompting

I inherited this report. Saved Data not checked. Does use 3 subreports, but issue existed before I added those. It prompts when I make ANY change to the report, including changing text field contents, moving fields to new location on report canvas, formatting change, etc., not just a change to the Record Selection Formula. Also occurs on other machines with CRW32.exe, not just my machine. Does not occur with any other report that I am aware of.

Thanks for any suggestions!