I'm using Mandrake 9.2 on a Compaq Presarion laptop.

Sound output is working fine (via mpg123) and aumix can set the volume controls.

I can't play or record sound from the microphone jack at the front of the laptop.

/proc/modules includes these modules:

via82cxxx_audio 19388 0
ac97_codec 12084 0 [via82cxxx_audio]
uart401 6404 0 [via82cxxx_audio]
sound 54888 0 [via82cxxx_audio uart401]
soundcore 3588 4 [via82cxxx_audio sound]

/etc/modules.conf has:

above snd-via82xx snd-pcm-oss
alias sound-slot-0 via82cxxx_audio

lspci -v says:

00:07.5 Multimedia audio controller: VIA Technologies, Inc. VT82C686 AC97 Audio Controller (rev 21)
Subsystem: Compaq Computer Corporation Soundmax integrated digital audio
Flags: medium devsel, IRQ 11
I/O ports at 1000 [size=256]
I/O ports at 1834 [size=4]
I/O ports at 1830 [size=4]
Capabilities: [c0] Power Management version 2


Turning up the "Mic" volume on aumix doesn't play the sound going to the mic input,
and recording from /dev/sound/dsp just gives a silent file (no error messages).

Any suggestions?

You should use

alsamixer as you seem to have alsa modules loaded in...

make sure that your mic is not muted..

note the MM on the top of the slider...

PS> you may have to scroll to the left a bit to find your mic setting.,..


Cheers,

Gary

alsamixer says:

alsamixer: function snd_ctl_open failed for default: No such file or directory

By the way, I should probably have pointed out that I am running kernel 2.4.27. But I tried rebooting to the old kernel (2.4.22-10mdk which comes with Mandrake 9.2) and got the same result.

I have just discovered that there is no sound coming out of the headphone socket on the front of the laptop (only the internal speakers). So we may be looking at a hardware problem here

Is your system capable of 6-channel (5.1) sound? If so, you will need to run Kmix, and in the "Advanced" section, see if you have "mic as Center/LFE" enabled. If so, disable it, that shoud get you your mic input back. Also, if you need line-in, "line-in as surround" toggles that.

Hope this is what you're looking for....

Its definitely not 5.1 channel sound: there isn't even a n "Advanced" section in Kmix!