Buddy Activity Stream Privacy

Before I drive myself nuts trying to find this solution myself, maybe someone here can set the records straight.

I have a network that has buddypress installed.
I have 3 sites on the network.

site 1 is accessible by admin only and is basically an admin only blog of private information.
site 2 is a client site where they blog about stuff too.
there's also the root level site, which is where buddypress pages are hosted.

All users are registered on the root site as well as their own specific site. So the user on site 2 cant view site 1 blog content only their own + buddypress pages on the root site.

Why is it that the site 2 user can see in the admin user's Activity stream the posts from the private blog (or at least the title, the post thumbnail and the post excerpt)

Is there a way to avoid this happening?

Our ideal situation is that we can set up a client community where clients can view activity streams but only see the content (and titles, excerpts) for the sites where the are a registered user.

Is this possible with Buddypress, or am I barking up the wrong tree :slight_smile:
thanks for any help. If this isnt possible then we'll need to shift our strategy.