Acrobat XI 11.0.03 - Combining Files - Bookmarks misbehaving

I'm combining about 90 PDF files to generate one large document.

Each document has a one or two tier bookmark hierarchy created via (Word--->PDF) using the ribbon Acrobat tools in Word 2013.

All the bookmarks are preserved as expected.

Acrobat creates a top level bookmark for each file by picking up the file name, again, as expected.

HOWEVER, for about most of those files that top level bookmark gets "meshed" with the first bookmark in the file itself. In other words, it points to the page where that first file bookmark points, regardless of how many pages deep in the document that first file bookmark points. Also, if I select that top level bookmark that was created when combining files, and change its action-destination property, to, let's say, point to page 31 of the combined document instead of page 34, then that first file bookmark also decides to point to page 31.

So, in short, the File Name bookmark points to the destination where the first bookmark in the file points, and those two bookmars are somehow "dependent".

Now I have to select each file name bookmark individually, move the view back to the page where it should have pointed (the first page of that file before it was combined) and reset the destination by right clicking on the bookmark in the bookmark panel.

This is time consuming, and I have more than one such large file to create.

What is going on?

(By the way, I thought of updating my Acrobat version, but I cannot find the "Check for Update" option under the Help menu).