XMarks Safari constantly re-downloads old bookmarks 2011 iMac, OSX Mavericks, latest updates.

I have used XMarks (Foxmarks) for years to sync between Chrome and Firefox, but now I'd like to add Opera and Safari to that mix.  Opera works just fine, but Safari refuses to play nicely and I can't figure out why.

I have two profiles, the "default" profile that Foxmarks originally created (mobile.foxmarks.com) and one that I created (Profile 1).  Both have the identical bookmarks in them at this point, as shown in my.xmarks.com.

Unfortunately, Safari keeps somehow finding my old bookmarks from years ago that are a complete mess, and re-downloading them into the browser.  The only positive is that I have disabled Automatic Synchronization in XMark's preferences for Safari, so that Safari will no longer then corrupt my "real" bookmarks in Chrome, Opera, and Firefox, with this ancient data.

My solution every time I notice this (seems to be every few weeks), is to force-download to Safari from the server, overwriting the local data.  This works, but of course kinda defeats the purpose of keeping them all in sync (I browse for different purposes in each browser [different projects] and so would like to be able to bookmark in any of them and know that they will all stay in sync).  Ideally I could let Safari auto-sync as well.

Why does this keep happening?  Where is Safari even getting this old data, since it's clearly not in my profiles on XMarks?  How can I get Safari to stop this and simply work like all the other browsers do with XMarks?

UPDATE:  

After my most recent re-overwriting of the local bookmarks, I then uploaded from my local machine to the server, overwriting the server bookmrakrs to ensure they should be identical.  A couple hours later I got a popup that says this:


  You restored or uploaded bookmarks from another computer to our
  servers. You can sync normally (the safest choice), or you can
  download the server bookmarks, overwriting your local bookmarks. Which
  do you prefer?


I'm given the choices of Sync, Download, or Cancel.  I took a chance on "Sync" and everything seems fine, I don't see the old bookmarks appearing in Safari.
I seem to have solved my issue, as it's been quite a while now and the problem has not reappeared.

First I turned off Safari XMarks' option to automatically synchronize, so that it wouldn't mess things up during this process.  Then t had to get my bookmarks in Safari all clean &amp; perfect, and once I had that I manually overwrote the server bookmarks with the copy in Safari.  Since then, my old "bad" bookmarks have not reappeared.  I suppose it's possible that Safari is quietly in the background still downloading and overwriting my local with the server bookmarks from time to time, but since the server copy is now correct, if that's happening, I don't notice.

Everything seems fine now, I can use/update bookmarks in Chrome and Safari and they all stay in sync, though there is a definite lag in time for them to pick up changes made from one another, that's just a fact of the way the software works it seems.