Disable member emails for specific levels.

my_pmpro_disable_member_emails.php

function my_pmpro_disable_member_emails($recipient, $email)
{
	$user = get_user_by('login', $email->data['user_login']);
	$level = pmpro_getMembershipLevelForUser($user->ID);
	
	$disabled_levels = array(1,2,3);	//update this to include ids of all levels you want to disable emails for

	if(!empty($level) && !empty($level->id) && in_array($level->id, $disabled_levels))
  		$recipient = NULL;	
	
	return $recipient;
}
add_filter("pmpro_email_recipient", "my_pmpro_disable_member_emails", 10, 2);