Internal microphone not working on a T420s

akuschki · 2012-03-18 12:40:07

Hi,

I have been googling a lot and reading the forums, but nothing seems to help. No matter what I do, the internal mic does not record any sound. I tried with pulseaudio and without, various options in alsa-base.conf, all kinds of settings in alsamixer, trying audacity, trying hda-analyzer etc. Nothing seems to work. But I know the hardware is not the problem because it worked when I tried Windows 7. The problem is not that my recording volume is very low, it is not recording anything at all.

I at a loss how to debug this. Can anybody give me a pointer which steps I need to take to find out where exactly the problem lies?

Cheers

Last edited by akuschki (2012-03-18 12:41:01)

akuschki · 2012-03-20 01:17:51

I can't possibly be the only person on the whole internets whose internal mic does not work under Linux? Heeelp.

ConnorBehan · 2012-03-20 01:52:32

I would start by disabling any sound server, making your ALSA configs default, loading as many snd modules as you can, pressing F4 in alsamixer to look at the capture controls and setting "Mic" to be the one that is captured from.

akuschki · 2012-04-14 11:45:27

Sorry for replying late, I have sunk so much time into this issue already that sometimes I need to take a break to keep my sanity. According to https://wiki.archlinux.org/index.php/Ad … are_loaded, the following output indicates that it is not a problem with the snd modules, right?

a ~$ lsmod | grep '^snd' | column -t
snd_hda_codec_conexant 46938 1
snd_hda_intel 23631 2
snd_hda_codec 92950 2 snd_hda_intel,snd_hda_codec_conexant
snd_hwdep 6389 1 snd_hda_codec
snd_pcm 74812 2 snd_hda_codec,snd_hda_intel
snd_page_alloc 7153 2 snd_pcm,snd_hda_intel
snd_timer 19544 1 snd_pcm
snd 59858 11 thinkpad_acpi,snd_timer,snd_pcm,snd_hwdep,snd_hda_codec,snd_hda_intel,snd_hda_codec_conexant
a ~$ ll /dev/snd
total 0
drwxr-xr-x 2 root root 80 Apr 14 13:18 by-path
crw-rw----+ 1 root audio 116, 6 Apr 14 13:18 controlC0
crw-rw----+ 1 root audio 116, 2 Apr 14 13:18 controlC29
crw-rw----+ 1 root audio 116, 5 Apr 14 13:18 hwC0D0
crw-rw----+ 1 root audio 116, 4 Apr 14 13:39 pcmC0D0c
crw-rw----+ 1 root audio 116, 3 Apr 14 13:36 pcmC0D0p
crw-rw---- 1 root audio 116, 1 Apr 14 13:18 seq
crw-rw----+ 1 root audio 116, 33 Apr 14 13:18 timer

Last edited by akuschki (2012-04-14 11:46:19)

akuschki · 2012-04-14 16:09:24

Just tried a ubuntu 12.04 live disk and it does not work there neither. It seems to work for other people with a T420s. Still, there must be some way to find out where exactly in the stack the problem is. Is there a way to read some kind of socket or register or serial port or binary something to ascertain that there is signal being received by the microphone?

Arch Linux

#1 2012-03-18 12:40:07

Internal microphone not working on a T420s

#2 2012-03-20 01:17:51

Re: Internal microphone not working on a T420s

#3 2012-03-20 01:52:32

Re: Internal microphone not working on a T420s

#4 2012-04-14 11:45:27

Re: Internal microphone not working on a T420s

#5 2012-04-14 16:09:24

Re: Internal microphone not working on a T420s

Board footer