I notice you are on version 1.25 of calibre, which probably means you are using a distro version. Distro versions are always horribly out of date, with a fast-moving program like calibre. You should really install the binaries distributed on the website:
http://calibre-ebook.com/download_linux
Or my auto-install-and-update script here:
https://www.mobileread.com/forums/sho...d.php?t=237233