Have you tried to use a recursive array_diff?
function arrayRecursiveDiff($aArray1, $aArray2) {
$aReturn = array();
foreach ($aArray1 as $mKey => $mValue) {
if (array_key_exists($mKey, $aArray2)) {
if (is_array($mValue)) {
$aRecursiveDiff = arrayRecursiveDiff($mValue, $aArray2[$mKey]);
if (count($aRecursiveDiff)) { $aReturn[$mKey] = $aRecursiveDiff; }
} else {
if ($mValue != $aArray2[$mKey]) {
$aReturn[$mKey] = $mValue;
}
}
} else {
$aReturn[$mKey] = $mValue;
}
}
return $aReturn;
}
the function is taken from here