Unusual Table Footer Problem

I am using Frame 9. I've had an odd table footer printing/display problem that I can't quite figure out.

Here's what happens:

I have a table that goes over about 4 pages. It has a header and footer. The header and footer are both set to repeat on every page. The footer is very distinctive, with a black fill and white letters. Several times I've opened the document to make edits (we're in the midst of a longer process) and, while scrolling through the pages, I'll notice that the footer isn't at the bottom of the page. Instead it will be somewhere in the middle or higher on the page. It isn't on top of a row (meaning, it isn't obscuring something beneath it, like a layers issue with InDesign or similar program). Other pages in the same table may or may not have the same issue, I've seen it both ways.

I thought maybe I had somehow mis-pasted a new row into the table and so I deleted the mid-page "footer," only to have the footer on all pages disappear. I hit the Undo button and the problem was miraculously fixed. Until I closed and opened the file again. I can repeat the fix with the Undo. I have printed it to a PDF before closing and reopening and had it create a PDF that looks correct.

All the basic table settings look correct. No amount of fiddling with them seems to have solved the problem.

Any ideas?