usb sound card

Before activate USB mic device, one must check the correct modules are loaded. See
http://wiki.audacityteam.org/index.php?title=USB_mic_on_Linux

• arecord --list-device
  card 0:  .............................
   ................................
  card 1:  usb blabla
  
• alsamixer -c 1
• using "TAB", select [Capture] or [All]
• L OR [SPACE], will activate your Capture device. Then you will see
  
   |      |
  L ----- R
  CAPTUR
• increase recording range by using arrows or other keys.