I am building an interface to mpg123 from another application using the Remote command interface. I have observed that if the FORMAT command is issued to get the audio sample rate (e.g. 44100) after a file is loaded but before starting playback, the mpg123 process will crash when playback is started. If the file is loaded and played, then paused, then FORMAT issued, playback will continue without error. I’ve duplicated this using a USB audio “card” as well as the build-in mcasp interface.
Linux BBB 4.4.30-ti-r64 #1 SMP Fri Nov 4 21:23:33 UTC 2016 armv7l GNU/Linux
mpg123 version: 1.20.1, installed using apt install mpg123 on BBB running jessie
Log: (inline descriptive comments added to actual log output is designated by //)
$ mpg123 -R -a default:Device // start mpg123 in “Remote command mode” with standard mcasp audio device
@R MPG123 (ThOr) v8 // response: normal startup message
LOADPAUSED ./my_file.mp3 // command: “LOADPAUSED/LP” - load a file (“my_file.mp3”) but do not begin playback
@I ID3v2.title:my_track // response: ID3 information…
@I ID3v2.artist:my_artist
@I ID3v2.album:my_album
@I ID3v2.year:2017
@I ID3v2.comment:12++
@I ID3v2.genre:Country & Folk
@P 1 // response: file loaded & paused, ready to begin file playback
FORMAT // command: “FORMAT” - get audio sample rate and channel count
@FORMAT 44100 2 // response: 44100 Hz, 2-channel
PAUSE // command: “PAUSE” - pause/un-pause
@P 2 // response: OK, playing file, but…
[alsa.c:230] error: Fatal problem with alsa output, error -5.
[audio.c:614] error: Error in writing audio (Success?)!
[mpg123.c:681] error: Deep trouble! Cannot flush to my output anymore!
Doing the same thing without issuing the “FORMAT” command works fine. Doing the same thing, but after loading file, beginning playback, then pausing, then issuing “FORMAT” command, then continuing playback (or seeking back to the beginning of the file and playing) works fine.
Any ideas how to resolve this, or repair it? I’ve searched and not found anything about this (most issues seemed to be related to alsa).
Thanks.