Recording problem: Heavy Static

[Jay Lauser]

Using a clean install of Maverick, I tried to record my voice. I was able to get it to record through both a microphone and through the built-in mics on my laptop. However, it also recorded heavy static, almost obscuring my voice. I was able to edit it out using Audacity, but doing so required so much noise removal that it messed up my voice. This occurred whether using the internal mics, or the two different external mics I tried.

It did not occur if I changed the recording to capture from Monitor of Internal Audio Analog Stereo: it captured it cleanly.

Any ideas?

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: alsa-base 1.0.23+dfsg-1ubuntu4
ProcVersionSignature: Ubuntu 2.6.35-22.33-generic 2.6.35.4
Uname: Linux 2.6.35-22-generic x86_64
NonfreeKernelModules: nvidia
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.23.
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: fidelitas 1523 F.... pulseaudio
 /dev/snd/pcmC0D0p: fidelitas 1523 F...m pulseaudio
Card0.Amixer.info:
 Card hw:0 'Intel'/'HDA Intel at 0xf8400000 irq 49'
   Mixer name : 'Realtek ALC268'
   Components : 'HDA:10ec0268,14c00025,00100003 HDA:10573055,10573055,00100700'
   Controls : 15
   Simple ctrls : 12
Date: Thu Nov 18 10:06:10 2010
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release amd64 (20101007)
PackageArchitecture: all
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.utf8
 SHELL=/bin/bash
SelectedCard: 0 Intel HDA-Intel - HDA Intel
SourcePackage: alsa-driver
Symptom: audio
Title: [Realtek ALC268] Recording problem
dmi.bios.date: 12/31/2007
dmi.bios.vendor: COMPAL
dmi.bios.version: 1.16
dmi.board.name: JFL92
dmi.board.vendor: -
dmi.board.version: IFT00
dmi.chassis.asset.tag: -
dmi.chassis.type: 10
dmi.chassis.vendor: No Enclosure
dmi.chassis.version: N/A
dmi.modalias: dmi:bvnCOMPAL:bvr1.16:bd12/31/2007:svn-:pnN/A:pvrN/A:rvn-:rnJFL92:rvrIFT00:cvnNoEnclosure:ct10:cvrN/A:
dmi.product.name: N/A
dmi.product.version: N/A
dmi.sys.vendor: -

[tsg1zzn (tsg1zzn)]

I believe "Internal Audio Analog Stereo" is the correct setting for your sound card's microphone input. If it works with this setting, then everything is as it should be, except maybe the defaults need changing so that it works out of the box.

[Jay Lauser (siremethmimetes)]

It records with that setting, but the quality is bad. The bug is the quality, not whether or not it records.

[tsg1zzn (tsg1zzn)]

In your description you wrote that the problem does NOT occur with "Internal Audio Analog Stereo", only with "Monitor". What is the input name that works correctly and what is the input name that has poor quality?

[Jay Lauser (siremethmimetes)]

My apologies for being unclear.

On Monitor it captured cleanly, but it didn't capture the input. It captured the audio going out (like if I had music playing on the computer, it recorded that). No static. No mic.

On Internal it captured from the mics, but had the heavy static. Yes static. Yes mic.

My deduction is that there is something about the software that messes with the input, since it isn't the recording hardware.

Does that help?

[tsg1zzn (tsg1zzn)]

Thanks, it's clear now. If you are sure the hardware is ok, I assume this is a driver problem (bug in alsa-driver).

[Jay Lauser (siremethmimetes)]

Do I need to attach additional information to help debug that?

[Daniel T Chen (crimsun)]

Can you reproduce this symptom after following https://wiki.ubuntu.com/Audio/InstallingLinuxAlsaDriverModules ?

[Jay Lauser (siremethmimetes)]

Thanks for the link! I went and followed those instructions, and the bug remains, so it looks like it is still up-river.

Is there some way to add more information on this by running some sort of debug command on alsa-driver or something?

[Marcus Tomlinson (marcustomlinson)]

This release of Ubuntu is no longer receiving maintenance updates. If this is still an issue on a maintained version of Ubuntu please let us know.

[Launchpad Janitor (janitor)]

[Expired for alsa-driver (Ubuntu) because there has been no activity for 60 days.]