Update 5: Although the website was down, all MP3 file downloads continued to be served and tracked without interruption.
Update 4: We've made it so this won't happen again, even if all the cache servers are offline.
Update 3: All services are now back.
Update 2: We've identified the issue (our host rebooted our cache servers leading to an issue where an incorrect configuration file was loaded).
Update: We are experiencing an outage affecting Fireside websites, and are working on the problem.
I am very sorry for the interruption of service!
-Dan