RSS feed items displayed multiple times

There are RSS feeds fetched up and displayed on site using RSS Multi Importer plugin. Feeds are displayed using shortcodes but they are being fetched by the plugin first and saved to the database.

On this page (and some other too, that's a test page) feed items are displayed 3 times. If you check "Feed Items" page in plugin conflict you'll find out that e.g. for "German" or "Bomb" phrases it finds the same feed items fetched twice (which is already wrong) but still - they're displayed 3 times on the page.