There is a strange bug in SSIS when exporting data to flat file. Although the problem seems frustrating, the workaround is pretty smooth.
If you find the TextQualifier attribute of the corresponding flat file connection manager, you will notice where the problem comes from.
All you need to do is to replace the malformed text "_x003C_none_x003E" with the correct one “<none>” (quotations for clarification).
Steve Wiseman has a clear and detailed explanation of the problem in his blog.