[Plugin: WordPress SEO by Yoast] XML Generation error

Any ideas why I would be getting this error when checking the XML file?

XML Parsing Error: XML or text declaration not at start of entity
Location: http://thevillageshealthsource.com/sitemap_index.xml
Line Number 2, Column 1:<?xml version=”1.0″ encoding=”UTF-8″?><?xml-stylesheet type=”text/xsl” href=”http://thevillageshealthsource.com/wp-content/plugins/wordpress-seo/css/xml-sitemap-xsl.php&#8221;?>
^

Thx.

http://ww.wp.xz.cn/extend/plugins/wordpress-seo/