Hi all
I am using Kubuntu 8.10, on an Asus Aspire 7730Z laptop. Sound playback is perfect since installation without any hassles, but recording is a different story.
Using alsamixer, I've found out that 'Front Mic' and 'Front Mic Boost' handle the built-in microphone on the top of the screen. I know this by scratching my finger on the mike, and hearing the feedback through the speaker. I can even make it squeal very loudly with audio feedback ;-). So that stuff works.
The simplest recorder for alsa is 'arecord', so I tried
arecord -fdat foo.wav
aplay foo.wav
There's nothing in the file, not the faintest whisper.
acer:/etc/modprobe.d$ arecord -l
**** List of CAPTURE Hardware Devices ****
card 0: Intel [HDA Intel], device 0: ALC888 Analog [ALC888 Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: Intel [HDA Intel], device 4: ALC888 Analog [ALC888 Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
I've tried with many options of -D hw:0,0 -D hw:0,4 -D plughw:0,0 etc... but still nothing in my foo.wav file.
I've also tried more complicated applications like audacity and ardour2 but still no luck.
My questions:
- Any specific pointers on how to proceed to get my recording working ? I know about www.alsa-project.org and http://alsa.opensrc.org and I can't find my problem solution there.
- How does the name 'Front Mic' in alsamixer relate to the channel designation hw:x,y?
- What is plughw:x,y vs hw:x,y ?
- How come the microphone is immediately piped to the speakers, how is that linked?
Thanks
Bart
P.S.
In /var/lib/alsa/asound.state I have the following sections related to 'Front Mic'
control.19 {
comment.access 'read write'
comment.type INTEGER
comment.count 2
comment.range '0 - 31'
comment.dbmin -3450
comment.dbmax 1200
iface MIXER
name 'Front Mic Playback Volume'
value.0 27
value.1 27
}
control.20 {
comment.access 'read write'
comment.type INTEGER
comment.count 2
comment.range '0 - 3'
comment.dbmin 0
comment.dbmax 3000
iface MIXER
name 'Front Mic Boost'
value.0 2
value.1 2
}
control.21 {
comment.access 'read write'
comment.type BOOLEAN
comment.count 2
iface MIXER
name 'Front Mic Playback Switch'
value.0 false
value.1 false
}
From one post on the web, I have two options in /etc/modprobe.d/
Edit: I've now also tried the same without these options, and the problem is exactly the same
---
My name is bart, I always use that to tag system config file changes
acer:/etc/modprobe.d$ grep -A3 bart *
aliases:# bart
aliases-alias snd-card-0 snd-hda-intel
aliases-alias snd-slot snd-hda-intel
--
alsa-base:# bart
alsa-base-#
alsa-base-options snd-hda-intel model=acer