This plugin can cause problems in the wp_head by adding html tags where they shouldn't be. For example, this is some code I found in my wp_head, and I had to adjust the title of the post to remove an acronym because the plugin was putting a span around it.
<link rel="alternate" type="application/rss+xml" title="What Is <span class="caps">SEO</span> Comments" href="http://techstudio.co/?feed=rss2&p=97" /></head><body class="body-class" id="loc-Mount Pleasant-SC">
As you can see, the span tag in the title attribute breaks the code there.
So this brings me to the suggestion, strip tags before passing the attritube to whatever code writes those link elements.