Audio recording from USB

Fri Jul 6 18:24:39 UTC 2018

On Fri, Jul 6, 2018 at 12:40 AM, Hans Petter Selasky <hps at selasky.org>
wrote:

> On 07/06/18 02:00, Kevin Oberman wrote:
>
>> Oops! Sorry of hte empty message made it through.
>>
>> On Thu, Jul 5, 2018 at 12:47 AM, Hans Petter Selasky <hps at selasky.org>
>> wrote:
>>
>> On 07/04/18 23:41, Kevin Oberman wrote:
>>>
>>> I have an Audio-technia turntable with USB output and I want to use
>>>> audacity to record from it. I have read the sound, mixer, and snd_uaudio
>>>> man pages, but am still unable to get the configuration correct. sndstat
>>>> shows the device (pcm4) but mixer only lists pcm0, the Conexant CX20590,
>>>> which is marked as default in sndstat.
>>>>
>>>> Messages on connection:
>>>> uaudio0 on uhub3
>>>> uaudio0: <BurrBrown from Texas Instruments USB AUDIO  CODEC, class 0/0,
>>>> rev
>>>> 2.00/1.00, addr 3> on usbus1
>>>> uaudio0: Play: 48000 Hz, 2 ch, 16-bit S-LE PCM format, 2x8ms buffer.
>>>> uaudio0: Play: 44100 Hz, 2 ch, 16-bit S-LE PCM format, 2x8ms buffer.
>>>> uaudio0: Play: 32000 Hz, 2 ch, 16-bit S-LE PCM format, 2x8ms buffer.
>>>> uaudio0: Record: 48000 Hz, 2 ch, 16-bit S-LE PCM format, 2x8ms buffer.
>>>> uaudio0: Record: 44100 Hz, 2 ch, 16-bit S-LE PCM format, 2x8ms buffer.
>>>> uaudio0: Record: 32000 Hz, 2 ch, 16-bit S-LE PCM format, 2x8ms buffer.
>>>> uaudio0: Record: 22050 Hz, 2 ch, 16-bit S-LE PCM format, 2x8ms buffer.
>>>> uaudio0: Record: 16000 Hz, 2 ch, 16-bit S-LE PCM format, 2x8ms buffer.
>>>> uaudio0: Record: 11025 Hz, 2 ch, 16-bit S-LE PCM format, 2x8ms buffer.
>>>> uaudio0: No MIDI sequencer.
>>>> pcm4: <USB audio> on uaudio0
>>>> uaudio0: HID volume keys found.
>>>>
>>>> Installed devices:
>>>> pcm0: <Conexant CX20590 (Analog 2.0+HP/2.0)> (play/rec) default
>>>> pcm1: <Intel Cougar Point (HDMI/DP 8ch)> (play)
>>>> pcm2: <Intel Cougar Point (HDMI/DP 8ch)> (play)
>>>> pcm3: <Intel Cougar Point (HDMI/DP 8ch)> (play)
>>>> pcm4: <USB audio> (play/rec)
>>>>
>>>> mixer -f /dev/mixer4 shows:
>>>> Mixer vol      is currently set to  75:75
>>>> Mixer pcm      is currently set to  75:75
>>>> No line or mic.
>>>>
>>>> I tried "cat /dev/dsp4.0" and got the expected stream of "junk" that
>>>> looks
>>>> like it is getting data from the turntable.  "junk" changes when I play
>>>> something, so I think the hardware is all working to some degree.
>>>>
>>>> Can anyone suggest where to go from here?
>>>>
>>>>
>>> Did you try:
>>> sysctl -a hw.snd.default_unit=4
>>>
>>> --HPS
>>>
>>
>>
>> Yes, but...
>>
>>> mixer
>>>
>> Mixer vol      is currently set to  75:75
>> Mixer pcm      is currently set to  75:75
>>
>> So mixer seems to "see" mixer4, but still only shows vol and pcm. No input
>> device. Bringing up the mate sound preferences, I only see the on-board
>> mic  for input, but see the USB device for output. I'm a bit baffled as to
>> why the mixer fails to any USB input even though the connection message
>> clearly shows that capability.
>>
>
> The mixer might not always have a node for input. You can try to dump the
> sysctl tree, grepping for pcm. There might be some hidden ones under .mixer
> .
>
> --HPS
>

I see:
dev.pcm.4.rec.vchanformat: s16le:2.0
dev.pcm.4.rec.vchanrate: 48000
dev.pcm.4.rec.vchanmode: fixed
dev.pcm.4.rec.vchans: 1

There is no indication that a "line" or any mixer input (rec) is created.
The only .mixer values are for play entries which exist in the CODEC chip,
but go nowhere:
dev.pcm.4.mixer.mute_1.desc: USB AUDIO  CODEC
dev.pcm.4.mixer.mute_1.max: 1
dev.pcm.4.mixer.mute_1.min: 0
dev.pcm.4.mixer.mute_1.val: 0
dev.pcm.4.mixer.vol_0_1.desc: USB AUDIO  CODEC
dev.pcm.4.mixer.vol_0_1.max: 0
dev.pcm.4.mixer.vol_0_1.min: -16384
dev.pcm.4.mixer.vol_0_1.val: -7261
dev.pcm.4.mixer.vol_0_0.desc: USB AUDIO  CODEC
dev.pcm.4.mixer.vol_0_0.max: 0
dev.pcm.4.mixer.vol_0_0.min: -16384
dev.pcm.4.mixer.vol_0_0.val: -7261

I am not familiar with the sound subsystem design, so I have no idea what
part should be doing this.

In a slightly unrelated issue, is any way to get the uaudio device to
disconnect when I unplug the device without killing Mate? The man page
describes this. I get continual messages:
pcm4: Waiting for sound application to exit!
pcm4: unregister: mixer busy

The mate-settings-daemon and mate-volume-control-applet programs keep
connections to uaudio open. I can kill the volume applet, but killing the
settings-daemon just results it a new settings-daemon starting and the
device not being desconnected. Restarting Mate does result in the device
being disconnected.

Just an annoyance, but one I'd prefer to live without.
--
Kevin Oberman, Part time kid herder and retired Network Engineer
E-mail: rkoberman at gmail.com
PGP Fingerprint: D03FB98AFA78E3B78C1694B318AB39EF1B055683