Ok, it's fixed, or I think so, I've just uploaded the new version, it will be available in a minute or so. Apparently there exists an issue between Visual Composer and strip_shortcodes WordPress hook which makes imposible to strip shortcodes generated by this plugin.
I solved the issue replacing the
strip_shortcodes hook by a regex, if someone looks for a similar solution, here's what I did:
I was stripping shortcodes and tags using this line:
$content = strip_tags(strip_shortcodes($content));
Which works for almost every kind of shortcode and tag I can imagine, but for some reason it didn't work with Visual Composer shortcodes, so I replaced that line by these two:
$content = preg_replace("/\[(.*?)\]/i", '', $content);
$content = strip_tags($content);
And that's it, the first line removes everything between square brackets (shortcodes) and the second one strip tags.
I'm marking this topic as resolved, feel free to change it if v3.1.6 doesn't solve your issue.