Here's my new audio horror story on Unix.

I bought a usb headset (headphone+microphone) yesterday.
I plug it in and it doesn't magically work so I dive into documentation and online posts.
Pavucontrol popped up, it is an application that let you interface with pulseaudio. It didn't work on my Arch machine and I decided to give it a try on my Debian box. It worked flawlessly.
After doing a diff of the pulse configuration files I found my issue, that's what worked for me:
It also automatically switches to the usb headset when connected.

But there was still an issue I couldn't hear any sound as a normal user. I was firing mplayer to test the audio and after hours of debugging the .mplayer/config had this faulty line:
I swapped alsa by pulse and this solved it.

Next on the list: MPD wasn't using my pulse configuration. As "I discovered in the manual", mpd lauches it's own instance of pulse when started as a global daemon and thus I had to switch from a global to a local setting.

Done... Still no sound.

I rechecked my .mpdconfig over and over again trying weird things that made no sense to finally find my issue:

I had those lines for the audio output. The first one being for the "artsy" in ncmpcpp and second for my pulse output.

However I didn't know that pulse had to listen on a TCP port to be usable from MPD localhost; the "server 127.0.0.1" in the above config.

Adding this line to /etc/pulse/default.pa made everything finally work.