Hi Abz,
many thanks for the prompt response. As I mentioned in my original post, if I insert that code snippet in functions.php it breaks every time the theme is updated (I have auto update turned on to be compliant with best practice)
I will investigate the Code Snippets add-in and see if that will help.
But I would strongly suggest that he team consider adding a checkbox in the admin interface, as it means anyone could use the feature without resorting to php and reduce the need for other add-ins to get code snippets working.
Regards.