have you installed the Player plugin? (mandatory! read the installation instructions http://www.joomlamusicsolutions.com/en/support/installation.html

Thanks, that got it. I'm also trying to use the JW Player module, and when I click on the popup link I'm getting this message:

Not Found

The requested URL /diamondunderground/undefined was not found on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

Any idea why it's doing that?

have you installed the CORE plugin as well...?

Ok thanks, I thought I did those plugins but I guess not. Now separate question...

I'm adding test comments on the front end, but it's not appearing in the 'Comments' tab in the backend. I've tried using facebook and disqus comments.

facebook and disqus will never appear on the backend... (precisely for that! they are Facebook and Disqus!!) the only ones you'll see in the backend are those introduced using the MC native comment system.

Ok, dare I ask how do I enable that? I've enabled built in comment system in parameters, but the only time I see comment boxes is when I enable facebook or disqus plugins.

"adding comment" feature will be visible only to registered users.