Hi I'm going to move your post to the Lesson forum because (unless I have misunderstood you) the term LInked media appears if you are using Moodle's Lesson activity. So to get rid of your linked media you need to click on your lesson and then edit the settings and delete the linked media. If I have misunderstood you then please post a screenshot showing where this linked media is on your course page so we can be clearer.
Lesson
Linked media showing on Navigation section
This discussion has been locked so you can no longer reply to it.