How to play 3gp audio files?

[John Magolske <listmail@b79.net>]

I'm looking for a way to play *.3gp audio files from the command line.
Mplayer doesn't seem to work:

    % Mplayer some-audio-file.3gp
    [...]
    Playing some-audio-file.3gp.
    libavformat file format detected.
    [lavf] Audio stream found, -aid 0
    ==========================================================================
    Opening audio decoder: [ffmpeg] FFmpeg/libavcodec audio decoders
    Cannot find codec 'libamr_nb' in libavcodec...
    ADecoder init failed :(
    ADecoder init failed :(
    Cannot find codec for audio format 0x726D6173.
    Read DOCS/HTML/en/codecs.html!
    Audio: no sound
    Video: no video

Any suggestions for alternate approaches, pointers on how & what to
install in terms of a codec, or maybe a way to convert these files
(ideally without transcoding degradation)?

These audio files were created by the android app "Voice Recorder".

TIA for any help,

John


-- 
John Magolske
http://B79.net/contact