At some point while futzing around with Nautilus (the Gnome file manager) on my house server, I unintentionally turned on the setting that will play an audio file if you hover the mouse cursor over its icon. I then discovered that while gstreamer-properties would play the test sounds just fine, gstreamer based programs like Totem or Rhythmbox stopped producing sound and the system sounds stopped as well. Once I turned the setting off everything produced sound again. Must test this on the laptop and also test to see if it breaks Flash (I was trying to watch a YouTube video at the same time and don't know if the problem was the website or the Nautilus setting).
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