ALSA: capture and playback (Unix Read/Write) - READ COMMENTS

Not implemented yet: ringtones, dtmf

#### Recommended play devices names (alsa-project.org)
#### http://www.alsa-project.org/main/index.php/DeviceNames
Device: #default --> capture : too much noise
		     playback : glitchs
		     dmix
	#plug:front  -->  playback almost perfect
		         capture :bad audio (noise noise noise !!!)
 		         dmix not enabled
 	#plug:rear  -->  doesn't exist on my sound card (Error: unknown PCM device)
	#plug:center_lfe --> idem
	#plug:side  --> idem

If there is multiple sound cards on your system, you can select the one you prefer like that:
  plug:front:0 select the card 0, 0 refers to the number in /proc/asound/cards.
  plug:front:Intel with the name of the card
My /proc/asound/cards:
0 [Intel          ]: HDA-Intel - HDA Intel
                      HDA Intel at 0xfdff4000 irq 23

##### Device names not recommmended (alsa-project.org)
These devices maps directly to the driver devices and doesn't handle an abstraction
	plughw -->  playback almost perfect
		    capture : noise plus weird behaviour
                    dmix not enabled
        hw  -->     playback : not audible ( maybe no resampling ?? no format conversion ??)
		    capture : XRUN mode
	            dmix not enabled