This is a response to VC 22 Stuart 5 ("Zygote speaks")...
I most certainly do NOT think of you as a zygote (although it IS rather a charming notion). I didn't really think that the problem was with your speaker volume, but as a good diagnostician I had to ask. Such things can and do happen, not only to zygotes but to fully formed, computer-literate organisms as well. I myself sometimes rant and curse at imagined demons for hours on end only to discover an unplugged keyboard (or something equally moronic).
The forces of entropy and darkness that infest all our creations and eventually bring each and every one of us down almost always manifest themselves as absurd and idiotic little pinpricks. Consider The Death of Ivan Ilyich in which a man helplessly watches his life drain away on account of an accident that occurred while hanging a curtain rod. It's always the little things that get us, and there should be no shame in admitting it.
As you can probably tell from the level of my oratory, I still have no idea what happened to your sound, why it only happened to you, and why it seems to have fixed itself for the time being. Ours is a mysterious universe.