I have a problem with jquery on my site since moment I installed shoutbox. When I installed jquery plugin, the shoutbox started working but slimbox stopped working. I had to turn on jquery plugin only on the front page and disable it on other pages.
I received answer from shoutbox developer:
Your template's old index.php does not follow Joomla's coding standards. You're also using Joomla's caching system which I'm really not a fan of. I've tested the Shoutbox notifications on both your default templates and also the Protostar (default Joomla 3.x) template, and both are working fine.
Sorry, but I am not able to support this template any longer. If you use a different template from an official template provider, or developer your own correctly, there won't be any issues. You need to fix everything up first.
I've had another developer look at your index.php file and he also agrees.