when i view the xml:
charttest_data1.php
I see that one of the lines has an accented character that is not displaying properly:
<label>Klassisk s�ng</label>
Does it show correctly ion the database?
If so try setting the connection to use the utf-8 character set.
In the connection file, locate the closing php tag:
?>
and add this code before it:
mysql_set_charset('utf8',$<your connection name>);
where <your connection name> is the name of your connection