mic seems to be there, but wont record for some reason

Cultist · 01-09-2011, 06:01 PM

Tried to use my laptop's built-in mic for the first time today, and it doesn't seem to be working. First tried to record with guvcview, which will capture video but no audio. It's dropdown box for audio input device shows an item named

Code:

HDA Intel: ALC663 Analog (hw:0,0)

In alsamixer I've set mic to max volume and unmuted. And I tried launching audacity as root to record, and again got nothing. This is as far as I was able to get with Google. Anyone able to offer some advice on how to turn on my mic?

Gavin Harper · 01-09-2011, 10:12 PM

Try using rexima.

In Rexima, boost "Mic" and "IGain"

enorbet · 01-10-2011, 03:12 AM

Greetz
From anything I see this is reported as a bug(s) as of late 2009. It seems some have been fixed but others have not. In my experience this is a common problem with all Linux sound servers and open source. Hardware support can be difficult and though it is improving, still many manufacturers are slow to release needed information. This is especially problematic when fundamental changes in hardware take place such as the increased adoption of HDMI. Certainly it is still true that "given enough eyes all bugs are shallow" but in very specific hardware support the process can be slow.

IMHO The best an average user can do is
1) look for an "asound.rc" file at alsa-projects that addresses the problem
2) upgrade kernel (if a newer one has a newer alsa release)
or
3) upgrade alsa from source
or
4) keep track of OSS4 progress and switch if support comes to it first

Good luck

Petri Kaukasoina · 01-10-2011, 03:21 AM

Quote:

Originally Posted by Cultist

In alsamixer I've set mic to max volume and unmuted.

Set mic to min volume and muted. Instead, put CAPTURE to max and set INPUT SOURCE to MIC.

Petri Kaukasoina · 01-10-2011, 03:23 AM

Quote:

Originally Posted by Gavin Harper

Try using rexima.

rexima is for oss.

unclejed613 · 01-10-2011, 06:15 AM

my alsa mixer has a CAPTURE button for the mic, make sure that's clicked if you don't have a capture button for the mic, you may have to enable it in the mixer setup.

Cultist · 01-10-2011, 06:50 AM

Quote:

Originally Posted by Petri Kaukasoina

Set mic to min volume and muted. Instead, put CAPTURE to max and set INPUT SOURCE to MIC.

k, how do I set input source? I don't see that anywhere

Petri Kaukasoina · 01-10-2011, 11:04 AM

In alsamixer, press Tab to change view until it is Capture. Keep hitting Cursor Right to cycle through the controls. Is there "Input source"?

If you can't find it then you don't have that control. Maybe you could give command amixer and attach its output here so we can see what controls you have.

T3slider · 01-10-2011, 12:45 PM

Turn up all volumes in alsamixer (and unmute everything) and turn up all capture controls (by pressing tab in alsamixer, as stated) and try recording. If it doesn't work, try muting the mic(s) in case ALSA is detecting the controls incorrectly. If that still doesn't work, you may have to try passing model options to the snd-hda-intel module. See /usr/src/linux-2.6.33.4/Documentation/sound/alsa/HD-Audio-Models.txt (in the ALC662/663/272 section). The possible models for your card:

Code:

ALC662/663/272
==============
  3stack-dig    3-stack (2-channel) with SPDIF
  3stack-6ch     3-stack (6-channel)
  3stack-6ch-dig 3-stack (6-channel) with SPDIF
  6stack-dig     6-stack with SPDIF
  lenovo-101e    Lenovo laptop
  eeepc-p701    ASUS Eeepc P701
  eeepc-ep20    ASUS Eeepc EP20
  ecs           ECS/Foxconn mobo
  m51va         ASUS M51VA
  g71v          ASUS G71V
  h13           ASUS H13
  g50v          ASUS G50V
  asus-mode1    ASUS
  asus-mode2    ASUS
  asus-mode3    ASUS
  asus-mode4    ASUS
  asus-mode5    ASUS
  asus-mode6    ASUS
  dell          Dell with ALC272
  dell-zm1      Dell ZM1 with ALC272
  samsung-nc10  Samsung NC10 mini notebook
  auto          auto-config reading BIOS (default)

Search the forums for "snd-hda-intel model" -- you should get *tons* of threads that deal with this. Google led me here -- a simple thread, but there are others that go into greater detail. This one goes into more detail. Autodetection is getting better with each ALSA release (and thus each kernel release), but sometimes it misses the mark and you need to specify the model manually. My old PC had to have the model specified manually for the mic to work (though the sound itself worked using most model options including the default). If it still doesn't work after trying each of those model options, then we will probably need a little more information, but this should get you started anyway.

Nille_kungen · 01-10-2011, 01:18 PM

In alsamixer you need to press F5 to see needed settings.

x-alien · 01-10-2011, 02:01 PM

On my Slackware 13.1 (kernel 2.6.37, sound card nVidia HDA) I have the following situation:

Skype identifies the microphone as alsa://default
MEncoder identifies the microphone as alsa://hw:0,0
VLC identifies the microphone as oss://dev/audio

VLC also accepts alsa://hw:0,0, but there is no sound.

Cultist · 01-10-2011, 02:03 PM

the only settings I can cantrol in alsamixer are Master, PCM, Mic, Capture, and Digital. All of which do nothing for my mic even when at max. There are two others that have no bar, both named S/PDIF. They aren't set to mute though.

impert · 01-10-2011, 02:29 PM

Hi,
I had a bit of trouble with microphones. Here's what works for me:

Quote:

Plug microphone into blue socket (line in) *******************IMPORTANT

Settings for recording:
Alsamixer:
Select F5: All
Master: 100
Line in: Doesn't matter
Mic: ~88% ***************Mic is the only input sliding control that matters.
Phone: Does not matter (?)
IEC958:MM *******************IMPORTANT
IEC958 C, F, R, U: Will all be 0 because of above.
Aux: Does not sem to affect recording.
Analog C, Analog F R S 80% or thereabouts **probably only C matters
Analog Source: Mic *************IMPORTANT Even though the mic is plugged into line in (blue)
Capture feedback: 0 **at any rate, less than about 70
Digital Source: i2s in ***************IMPORTANT
Shared Mic/Line in: Mic in ***************IMPORTANT
Mic is the only sliding control that matters.
Others: Analog Source: Mic Digital Source i2s in Shared Mic Mic in
Microphone MUST BE IN LINE IN in spite of the above.

Sound recorder.
Record as CD quality, lossy .ogg
In Sound preferences/Input:
Output Volume: 100%
Input Volume: unamplified can be 100%
Connector: Analog Microphone/Microphone
choose a device for Sound input: CA0106

/Output:
Choose a device for output: CA0106

In Audacity:
Preferences/Devices:
Host: ALSA
Playback Device: default
Recording Device: default
Channels: 2 (stereo)
Preferences/Playback: (times) 3 1 1 1 15
Preferences/Recording:Overdub ticked, Latency Audio to buffer 100 ms. Latency correction -130 ms.
Sound activated recording not ticked.

Note that my sound card uses the snd_ca0106 module - you seem to use hda_intel; and that I only have analog input and output. The counter-intuitive bit is the fact that the microphone must be plugged into the line in socket, and the "analog source" must be MIC.
Hope this helps.

T3slider · 01-10-2011, 02:35 PM

In any normal circumstance the line in connector should *not* be used for an analog microphone...the signal produced from microphones is very low and must be amplified for it to be usable (and mic inputs usually undergo hardware amplification). Line in inputs are for sources that do not need amplification. If you use a line in input for a microphone you will likely have to use software amplification to boost the signal, which will result in worse quality than simply using the microphone input and setting it up ALSA correctly to use it.

Skaperen · 01-10-2011, 02:35 PM

Quote:

Originally Posted by enorbet

Greetz
From anything I see this is reported as a bug(s) as of late 2009. It seems some have been fixed but others have not. In my experience this is a common problem with all Linux sound servers and open source. Hardware support can be difficult and though it is improving, still many manufacturers are slow to release needed information. This is especially problematic when fundamental changes in hardware take place such as the increased adoption of HDMI. Certainly it is still true that "given enough eyes all bugs are shallow" but in very specific hardware support the process can be slow.

IMHO The best an average user can do is
1) look for an "asound.rc" file at alsa-projects that addresses the problem
2) upgrade kernel (if a newer one has a newer alsa release)
or
3) upgrade alsa from source
or
4) keep track of OSS4 progress and switch if support comes to it first

Good luck

The many layers of software don't make it any easier. I have a need which involves writing my own program to capture sound samples in real time. Too many APIs makes this a challenge to figure out what to do. It REALLY should have been just a matter of opening the right device, doing some fcntl calls to set it up (that's where a library could help), and then many reads in a loop. If an API would be at least that simple, it would be good enough.