Debian Stretch
Audacity 2.1.2
Instelled from Debian repos
I have this MP3 file which Audacity insists to open as a mono file. Other MP3 files are opened just fine in stereo. Identifying the MP3 with mplayer:
jlinkels@donald-pc:~$ mplayer -identify -frames 0 bonfm_1567897498-1567901521.mp3
MPlayer 1.3.0 (Debian), built with gcc-6.2.1 (C) 2000-2016 MPlayer Team
do_connect: could not connect to socket
connect: No such file or directory
Failed to open LIRC support. You will not be able to use your remote control.
Playing bonfm_1567897498-1567901521.mp3.
libavformat version 57.56.101 (external)
Mismatching header version 57.56.100
ID_AUDIO_ID=0
Audio only file format detected.
Load subtitles in ./
ID_FILENAME=bonfm_1567897498-1567901521.mp3
ID_DEMUXER=audio
ID_AUDIO_FORMAT=85
ID_AUDIO_BITRATE=192000
ID_AUDIO_RATE=44100
ID_AUDIO_NCH=0
ID_START_TIME=0.00
ID_LENGTH=4029.00
ID_SEEKABLE=1
ID_CHAPTERS=0
==========================================================================
Opening audio decoder: [mpg123] MPEG 1.0/2.0/2.5 layers I, II, III
AUDIO: 44100 Hz, 2 ch, s16le, 192.0 kbit/13.61% (ratio: 24000->176400)
ID_AUDIO_BITRATE=192000
ID_AUDIO_RATE=44100
ID_AUDIO_NCH=2
Selected audio codec: [mpg123] afm: mpg123 (MPEG 1.0/2.0/2.5 layers I, II, III)
==========================================================================
AO: [pulse] 44100Hz 2ch s16le (2 bytes per sample)
ID_AUDIO_CODEC=mpg123
Video: no video
Starting playback...
Which looks a lot like stereo. FWIIW, I recorded this with ffmpeg from a live radio stream. When playing the stream in Mplayer it also identifies as stereo.
mplayer http://162.244.80.21:6482
<snip>
Bitrate: 96kbit/s
Cache size set to 320 KBytes
Cache fill: 10.00% (32768 bytes)
Audio only file format detected.
==========================================================================
Opening audio decoder: [mpg123] MPEG 1.0/2.0/2.5 layers I, II, III
AUDIO: 44100 Hz, 2 ch, s16le, 96.0 kbit/6.80% (ratio: 12000->176400)
Selected audio codec: [mpg123] afm: mpg123 (MPEG 1.0/2.0/2.5 layers I, II, III)
==========================================================================
AO: [pulse] 44100Hz 2ch s16le (2 bytes per sample)
The same application also records other radio streams and stores them in MP3. Those files are correctly opened in stereo.
What can I do to see why Audacity opens this file in mono?
jlinkels