A problem with a disappearing stick blogpost on blogiste since upgrade t

Hello: I've got an interesting problem I'm not able to solve. I run a site that aggregates feeds from many different blogs onto our site (we have not run Multisite - just a single site that is using Feedwordpress to bring feeds in).

On 3.6.4, I was able to post a "local" post at the top of the centre part of the page and sticky it there so it didn't filter down off the main page as new feeds came in. It would sit there as long as I wanted.

Since upgrading to 3.6.7 however, I've had an annoying problem. I post the same local "sticky" post at the top, but after the next polling of sites, the local sticky post completely disappears. Confounding me further, it gets replaced by a syndicated external feed at the top of the page (which when I go into the dashboard of WP and click "edit", it's been checkmarked as the sticky post, which I obviously never did), and the local post I've done has compeltely disappeared off of the site into apparent internet oblivion.

I don't want to completely blame 3.6.7, as it could very well be Wordpress doing it, or perhaps doing it in conjunction with the theme, but all I know is that this didn't occur on 3.6.4... so I'm kind of curious if any of you had any suggestions as to what might be causing this bit of quirkyness.

Thanks for any help.
Scott