# How to set up an external USB sound card, focusrite scarlet 8i6 ?



## Alain De Vos (Sep 1, 2019)

The soundcard looks to be detected by the kernel ,
# cat /dev/sndstat
returns :  pcm3: <USB audio> (play/rec)
But when I do,
# cat /dev/random > /dev/dsp3.0
I hear no sound

I'm missing "qasmixer", a small little program which allows in linux to set all mixer settings. The program dsbmixer gives me only two nobs , "vol" and "pcm".
To make life complicates, configuring sound, many things are possible e.g. jack,oss,portaudio,pulseaudio,sdl,sndio.
When I start jack, the error given is jackd unknown driver alsa.
Another error is : cannot create shm registry segment (Cannot allocate memory)
But which driver and interface should i put in qjackctl ?
What to put in rc.conf ? [currently I only have, sndiod_enable="YES"]
My end goal would be to  make the program lmms working, with midi and with low latency.
Can the soundcard be made to work ?


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## George (Sep 2, 2019)

It should be like this:
1. You plug in your usb soundcard.
2. You check whether it is detected with `cat /dev/sndstat`
3. You set it to default with `sysctl hw.snd.default_unit=3`. (3, because your log says "pcm3".) Now any program will direct the sound to that soundcard.
4. You adjust the volume with `mixer`.


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## Alain De Vos (Sep 2, 2019)

I'll add hw.snd.default_unit=3 to sysctl.conf , reboot and give it a try.

Nope, no sound at all.
cat /dev/random > /dev/dsp sounds nothing !!
Some boot log messages:
uaudio0: No HID volume keys found
uaudio0: Play: 44100 Hz, 12 ch, 32-bit S-LE PCM format, 2x8ms buffer.
uaudio0: Record: 96000 Hz, 8 ch, 32-bit S-LE PCM format, 2x8ms buffer.

Some alsa info:
# aplay -l :
> no soundcards found.
# aplay -L
> null , pulse, oss

Mixer is ok:
# mixer
Mixer vol is currently set to  97:97
Mixer pcm is currently set to  97:97

Using jack might be an option for having sound. It works with no realtime mode.
But jackd only seems to start when i use oss as driver not with alsa
But no sound. Deadbeef,audacious,lmms seem to be unable to play to jack

Last i tried gmerlin_alsamixer , it's a good mixer but it could not find alsa devices ...


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