Shuffle posts on main (every refresh)

generally, try to use 'pre_get_posts'
http://codex.ww.wp.xz.cn/Plugin_API/Action_Reference/pre_get_posts

start by creating a child theme of ‘surfarame’ and create a functions.php;

add for example (only include the php tags in a totally new functions.php):

<?php
function randomize_blog_posts( $query ) {
    if ( $query->is_home() && $query->is_main_query() ) {
	$query->set( 'orderby', 'rand' );
	}
	return $query;
}
add_action( 'pre_get_posts', 'randomize_blog_posts' );
?>

http://codex.ww.wp.xz.cn/Class_Reference/WP_Query#Order_.26_Orderby_Parameters

any theme specific questions should be asked in the theme’s forum at
http://ww.wp.xz.cn/support/theme/surfarama

is your child theme activated?

can you provide a link to your site to illustrate the behaviour?

are you using any cache plugins?