Plugin creates issues with toggle title jquery

It seems the active theme (WCA) of your website is using an old and vulnerable jQuery version (1.6.2)…

http://www.wcagroup.com.au/wp-content/themes/WCA/js/jquery-1.6.2.min.js

Because of this it might be you enabled the iTSec plugin Enqueue a safe version of jQuery setting in the WordPress Tweaks section of the Settings page.
It unloads the current WCA theme jQuery (1.6.2) version and then loads the standard jQuery version (1.11.3) included with WordPress 4.3.

http://www.wcagroup.com.au/wp-includes/js/jquery/jquery.js

This possibly breaks your WCA theme jQuery functionality for unknown reason (most likely incompatibility).

If you enabled the iTSec plugin Enqueue a safe version of jQuery setting try and disable it (if possible).
Since your current active theme (WCA) is using a known vulnerable jQuery release (1.6.2) it is recommended to update\migrate the WCA theme jQuery functionality to 1.6.3 or preferably the latest jQuery release (1.11.3).

All of the above is just theory and it is therefore possible that it is not entirely accurate. To actually see what exactly happens you would need to activate the iTSec plugin and enable the Enqueue a safe version of jQuery setting (if not already).

dwinden