Edit citation - Exclude 'Author'/'Year' - changes to one citation caused similar changes elsewhere in the document

Hi,

I am using Endnote X.0.2 with Word 2004, on a Mac OS X. I had no problems previously using Endnote on a PC at school. But using my computer now, I am experiencing frustration when I make changes to one specific citation, Endnote starts scanning the entire doc (which slows everything down) and automatically make changes to other citations as well. Anyone knows how to fix this? Or, can this be fixed?

Many thanks!