FC6 Mic does not work, although playback works

[amitbhatia]

* FC6, sound playback works, but sound recording (mic) does not work on SB450 chipset. I used arecord to record a wav file. It did not give any error while recording, but playback using aplay, seems to output some kind of background noise only.
* Mic device works, since I tested it on another windows box.
* alsamixer settings seem ok (default).
* Although I did a yum update on alsa-lib and alsa-utils, but /proc/asound/version still shows the original 1.9.12rc1.
* Dmesg has lot of hda_codec invalid lines

What am I missing here to make the sound recording work properly ?
================================================== =======

> /sbin/lspci
00:14.2 Audio device: ATI Technologies Inc SB450 HDA Audio (rev 01)

> rpm -q alsa-lib
alsa-lib-1.0.14-0.1.rc1.fc6
> rpm -q alsa-utils
alsa-utils-1.0.14-0.2.rc1.fc6

/proc/asound > cat version
Advanced Linux Sound Architecture Driver Version 1.0.12rc1 (Thu Jun 22 13:55:50 2006 UTC).


------- dmesg --------
l 0:7fff
hda_codec: invalid dep_range_val 0:7fff
hda_codec: invalid dep_range_val 0:7fff
hda_codec: invalid dep_range_val 0:7fff
...


> arecord -l
**** List of CAPTURE Hardware Devices ****
card 0: SB [HDA ATI SB], device 0: HDA Generic [HDA Generic]
Subdevices: 1/1
Subdevice #0: subdevice #0

> arecord -d 5 -t wav foo.wav

> aplay foo.wav

> cat /etc/modprobe.conf
alias eth0 8139too
alias scsi_hostadapter sata_sil
alias snd-card-0 snd-hda-intel
options snd-card-0 index=0
options snd-hda-intel index=0
remove snd-hda-intel { /usr/sbin/alsactl store 0 >/dev/null 2>&1 || : ; }; /sbin/modprobe -r --ignore-remove snd-hda-intel


> lsmod | grep snd
snd_hda_intel 22613 1
snd_hda_codec 154049 1 snd_hda_intel
snd_seq_dummy 8133 0
snd_seq_oss 37185 0
snd_seq_midi_event 11841 1 snd_seq_oss
snd_seq 57137 5 snd_seq_dummy,snd_seq_oss,snd_seq_midi_event
snd_seq_device 12621 3 snd_seq_dummy,snd_seq_oss,snd_seq
snd_pcm_oss 46561 0
snd_mixer_oss 20545 1 snd_pcm_oss
snd_pcm 80325 3 snd_hda_intel,snd_hda_codec,snd_pcm_oss
snd_timer 27077 2 snd_seq,snd_pcm
snd 57029 12 snd_hda_intel,snd_hda_codec,snd_seq_oss,snd_seq,sn d_seq_device,snd_pcm_oss,snd_mixer_oss,snd_pcm,snd _timer
soundcore 14113 1 snd
snd_page_alloc 14281 2 snd_hda_intel,snd_pcm

====================

[amitbhatia]

Update:
If I tweak a bit with the alsamixer settings and speak very loudly with the mic very very close to my mouth, and then record using arecord, then when i replay using aplay, I can hear my sound back, but very faint and with lot of background static noise.

The same mic, works fine with windows box, and also with another old toshiba laptop running FC3 and a non-intel sound chip.

So there might be some alsa setting which I am missing.

I remember reading in some post about line-in vs mic as input for alsa. Does anyone know what else can I try here ?

[amitbhatia]

Final Update:
I upgraged to kernel 2.6.22.7-57.fc6 and the mic is working now.