BuddyPress.org

I had some issues with this earlier too, using the code supplied in this thread should clear up your issue.

Here’s the code if you’re unable to click the link for some reason. You should put it in your bp-custom.php file.

function toa_check_page_reqiurement_and_lie_to_buddypress ($is, $component) {
    global $bp;
    if ($is || "activity" !== $component) return $is;
    if ((defined('BP_GROUPS_SLUG') && bp_is_groups_component() && 'activity' == $bp->current_action)){
        return true;
    }
    return $is;
}
function toa_setup_activity_filter () {
    add_filter('bp_is_current_component', 'toa_check_page_reqiurement_and_lie_to_buddypress', 10, 2);
}
function toa_teardown_activity_filter () {
    remove_filter('bp_is_current_component', 'toa_check_page_reqiurement_and_lie_to_buddypress', 10);
}
add_action('bpfb_init', 'toa_setup_activity_filter');
add_action('bpfb_add_cssjs_hooks', 'toa_teardown_activity_filter');