ffmpeg -i lekeitio.mp4 -acodec libmp3lame -ab 192k lekeitio.mp3
ffmpeg version 0.8.3-4:0.8.3-0ubuntu0.12.04.1, Copyright (c) 2000-2012 the Libav developers
  built on Jun 12 2012 16:37:58 with gcc 4.6.3
*** THIS PROGRAM IS DEPRECATED ***
This program is only provided for compatibility and will be removed in a future release. Please use avconv instead.

Seems stream 0 codec frame rate differs from container frame rate: 47.95 (5994/125) -> 23.98 (24000/1001)
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'lekeitio.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 1
    compatible_brands: isomavc1
    creation_time   : 2012-09-23 18:38:17
  Duration: 00:03:21.15, start: 0.000000, bitrate: 2650 kb/s
    Stream #0.0(und): Video: h264 (High), yuv420p, 1280x720 [PAR 1:1 DAR 16:9], 2490 kb/s, 23.98 fps, 23.98 tbr, 24k tbn, 47.95 tbc
    Metadata:
      creation_time   : 2012-09-23 18:38:17
    Stream #0.1(und): Audio: aac, 44100 Hz, stereo, s16, 157 kb/s
    Metadata:
      creation_time   : 2012-09-23 18:38:18
Unknown encoder 'libmp3lame'