So everything was working correctly (and had been for months) until:
I was playing music in Banshee and switching gnome sound settings from "Logitech Wireless Headset Analog Stereo" to "Built-in Audio Analog Stereo" and my finger stuttered a bit on the mouse. As a result I switched back and forth very quickly between the two options a number of times, and the music stopped. Banshee still looks like it's playing, but no sound comes out of the speakers (headset or standard).
What I've tried:
Searching lots, haven't found much that applies.
Removing and reinstalling Banshee via Synaptic (predictably made no difference).
Playing a song in Rhythmbox - same issue as Banshee, looks like its playing on the screen but no sound comes out.
Playing sound through Chrome (youtube videos, google play music) - works.
Playing an MP3s through VLC or Audacity - works.
Using TS3 - works.
So I conclude that I broke something not Banshee specific but not general enough to apply to all MP3 playing or other sound. I am extremely new to tracking down problems in Linux and all I can think of to do is:
1) Remove and reinstall Banshee's dependencies. This looks like it would break lots of stuff, so I didn't do it.
2) Reinstall Debian. This would probably work, but seems like overkill and I would prefer to avoid having to retweak everything again.
3) Ask for help! Any suggestions? Requests for other information that will help identify the problem?
What I have:
Debian stable with some backports
uname -a = Linux debian 3.2.0-4-amd64 #1 SMP Debian 3.2.60-1+deb7u3 x86_64 GNU/Linux
Gnome 3.4.2
Banshee 2.4.1
Rhythmbox 2.97
Chrome Version 38.0.2125.104 (64-bit)
Teamspeak 3 (v3.0.16)
VLC 2.1.2
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