Our support is here for our core products, not debugging your admin console. I suggested contacting your host, did you contact them? The problem is either something you have installed or a configuration problem on your server; it is not related to our products.
I have never heard of SoundCloud. If you are referring this plugin:http://extensions.joomla.org/extension/soundcloud-content
I see no reason why it wouldn't work, but we can't test every extension on the Joomla market.