Sound notification

Problem: Sound worked at the beginning of install, but after testing out my function keys (Fn+3, for example) to adjust the volume, the sound stopped working and the function keys still didn't do anything other than display the notification that they should be working.

Solution: Somehow I had been adjusting an imaginary sound output device or something. I click the speaker icon in the upper right-hand corner > Volume Control > then tinkered around until I picked the appropriate device (there was more than one at the time, now there's only one... don't ask me how). Then after some forum searching I found that the Fn keys were adjusting that *imaginary* speaker. On the #! forums, pashman supplied the ultra useful code that makes my Fn keys only adjust my active speaker, instead of the imaginary one:

 xfconf-query -c xfce4-mixer -p /active-card -s 'PlaybackBuiltinAudioAnalogStereoPulseAudioMixer'