If you disable the Auto Link Titles add-on, does the problem go away?
I can't think why it would come back, the specific circumstances that were at play before, are no longer relevant if you have upgraded to XF 1.4.9.
If the problem does go away with disabling that add-on then you should continue the discussion in the thread for that add-on. Otherwise, we'll need some more information, e.g. specific RSS feed URL and a list of other add-ons installed.