My social sharing plugin adds buttons to all the Custom Post Widget areas
If your social media sharing plugin adds buttons to the widget areas you could check the 'Do not apply content filters' checkbox. Note that when this is done, WordPress will also stop adding paragraph tags to your text, so use this setting with caution. It is much better to ask the developer of the social media sharing buttons plugin to correctly use the content filters (see http://pippinsplugins.com/playing-nice-with-the-content-filter/).
I did that and it works fine. You should look into that.
BTW, the forementioned custom post type DOES NOT appear anywhere on the YARPP settings page, ergo I don't have (or I have not found) the option to turn it off for that custom post type.