Oracle Audit Trail XML files using XML, Extend, problems with CLOB parsing

Using Oracle 12 to genereate Audit Trail XML, Extended files. Working fine in most cases, but there are some columns that should be audited, of type clob. When parsing the Oracle 12 generated xml file the clob filed contain characters that mess up the parsing of the XML format. Is there a workaround to get Oracle to put out the clob in more XML friendly format - I recall from memory that it used to be som [CDATA] elements.

(the reason to make use of clob in this case is performance so I have right now conflicting requirements performance and audit of the same data)