I use my dropbox account on both my macbook and a PC (Windows) at work. In both computers, I have installed the Dropbox App so I can sync all my folders. It does sync, but the problem is that it does not seem to be selective to the files that were modified. It syncs all the 3000 files I have in the Dropbox folder and it takes very long!!! Is it normal or is there something I can do so it will only sync files and folders that were changed somehow?