We've recently become aware of an issue with our streaming and on-demand audio players that prevent them from playing in certain browsers. Here is an example of how to make our streaming player re-appear on Firefox browsers:
Find the small 'plug-in' icon (looks like a small Lego block) in the address/location bar at the top left of your browser and click an option to allow plug-ins on our site. Although our site has a non-flash player available, some browsers are still blocking our entire player. Enabling Flash on our site only is harmless, and (for now) the easiest way to get the audio players working again. We are in contact with our site developers to try to improve the way this works in the future.