Open purple-mountains opened 6 years ago
To run sndiod from systemd, we cannot have
User=sndiod / this is wrong /
in sndiod.service
sndiod can be run either as any local user, or root, and not user "sndiod".
Either set
User=root
or remove User, defaults to root, on ARCH Linux.
Thank you so much! Finally got it working
I've found a way to improve the latency. It's still not perfect, but may be acceptable for some playing say Touhou in wine. Set both sndiod and aucat to use a buffer size of 512 (-b 512
). This should give you a latency close to 20ms.
How to get OpenBSD sndio working through ALSA on Linux
I used ARCH Linux
$ sudo pacman -S sndio
$ cat /etc/conf.d/sndiod OPTS="-f rsnd/1"
Assumes your bdwrt5677 card is the second device. If it's the first device, use
OPTS="-f rsnd/0"
but you won't get full audio from 0-max volume, on say mplayer or mpv.
Try it as an exercise - change your index in the .conf file in /etc.modprobe-d/, and notice the lower volume range to be much louder when it's our second device, versus setting it as the first device, "...index=0".
Start sndiod as user or root
$ sndiod -dddd -f rsnd/1
$ sudo sndiod -dddd -a on -f rsnd/1
For some reason, I need the "-a on" flag when starting it as root.
If I try
$ sudo sndiod -dddd -f rsnd/1
sndiod won't open it's first device when called upon to play audio, sndiod first device, snd/0, is mapped to rsnd/1 - our bdwrt5677 card.
If I try
OPTS="-a on -f rsnd/1"
in /etc/conf.d/sndiod, and start it through systemctl, sndiod won't open snd/0 for some reason. It won't open snd/0 either, if I try "-a off", or no -a option. Starting it through systemctl seems to be broken, or I'm missing something.
In the ARCH install, I manually added /var/lib/sndiod - doesn't seem to create it, on installation.
I only get success starting it as the same user, or sudo sndiod with -a on.
A copy of .asoundrc, see below, was made to /etc/asound.conf whilst getting sndiod to start via systemctl.
Thanks to http://billauer.co.il/blog/2014/04/alsa-pipe-playback-capture/ for hints on creating my asound.conf file. I couldn't work out why I was getting scrambled noise, till I read it.
$ cat $HOME/.asoundrc
pcm.sndio { type asym playback.pcm "sndio-play"
}
pcm.sndio-play { type plug slave { pcm "sndio-raw" rate 48000 format s16_le channels 2 } }
pcm.sndio-raw { type file slave.pcm null
} pcm.default sndio
Note: We need "channels 2" in the config, else we get scrambled output, like it's played at twice the speed. Try commenting it out, and hear the difference.
$ aplay -L
should show our new OpenBSD sndio PCM device
If you don't want sndio as the default just comment out "pcm.default sndio"
Test it works
$ aplay -D sndio -i /usr/share/sounds/alsa/Side_Right.wav $ aplay -D default -i /usr/share/sounds/alsa/Side_Right.wav $ aplay -i /usr/share/sounds/alsa/Side_Right.wav
and watch the messages scroll in the window we started sndiod.
mplayer doesn't sink audio / video in time, but it illustrates sndio via ALSA works.
$ mplayer -ao alsa:device=sndio _VIDEO_AUDIO_FILE
if sndio is our default device
$ mplayer -ao alsa _VIDEO_AUDIO_FILE
Enjoy!