[Ted S]

Open the file lgvdb.php and replace

$vbulletin->db->query_write("
  DELETE FROM " . TABLE_PREFIX . "lgv
  WHERE (lastactivity + (". $vbulletin->options['lgvcleardays'] ." * 86400)) < ". TIMENOW ."
 ");

With code

$vbulletin->db->query_write("
  DELETE FROM " . TABLE_PREFIX . "lgv
  WHERE (lastactivity + (30 * 86400)) < ". TIMENOW ."
 ");