Object appearing in HTML table of contents

I’m having an issue with my HTML generated table of contents.

Basically, I’ve included an image that appears beneath each chapter title following instructions here: genelempp.wordpress.com/2013/02 … -headings/

On my Kindle when I open when I press the ‘Go To’ button, I can see the word “OBJ” after each table of contents entry.

How can I fix?

See screenshots. The first one shows the issue and the second shows the image I use at the start of each chapter