A new WPRadio plugin version is available (1.0.4) which is upgraded to be compatible with the new version of Caster.fm API which is now called Caster.fm Cloud.
Please update the plugin to continue using WPRadio:
WPRadio – WordPress Radio Streaming Plugin – WordPress plugin | WordPress.org
To learn more about the new Caster.fm Cloud:
Free Cloud Stream Hosting – Caster.fm