Some themes may have badly coded pagination filters, which break when WPSSO is activated. If this is the case with your theme, you may try adding the following to your theme's functions.php file:

 

add_filter( 'redirect_canonical', 'wpsso_disable_redirect_canonical' );

function wpsso_disable_redirect_canonical( $redirect_url ){
    if ( is_front_page() )
        $redirect_url = false;
    return $redirect_url;
}