how to hide Endnote reference updates when Tracking Changes?

In Mac Word 2011 (and 2008), whenever I update the bibliography, each reference becomes marked as a Tracked Change by author “Unknown”. I’d like to only see tracked changes that real people have made, not the ones changed every time the bibliography is updated. Oddly, on the Track Changes dropdown menu where I can say which Reviewer’s changes are shown, “Unknown” doesn’t show up as one of the options and I can’t hide those. Anyone know how Endnote’s changes can be set not to show up as Tracked?