shortcut:
  [tab]       : shuffle url list
  [space]     : stop playing
  left arrow  : prev. song in url list
  right arrow : next song in url list
  up arrow    : increase volume
  down arrow  : decrease volume  
  [ctrl] + c  : toggle sound compressor
  [ctrl] + s  : search in url list
  [ctrl] + f  : open files in local list
  [ctrl] + d  : open folder in local list
  [ctrl] + l  : toggle show/hide url list 
  {l = lower case from L}