[12.04 64-bit] Acer C7 microphone input can't be captured by applications

Bug #1093395 reported by Nicholas Kirchner on 2012-12-24

This bug report will be marked for expiration in 26 days if no further activity occurs. (find out why)

This bug affects 4 people
Affects Status Importance Assigned to Milestone
alsa-driver (Ubuntu)

Bug Description

Installed ChrUbuntu on the new Acer C7 Chromebook using the instructions here: http://chromeos-cr48.blogspot.com/2012/04/chrubuntu-1204-now-with-double-bits.html

A commenter at http://chromeos-cr48.blogspot.com/2012/11/looking-for-acer-c7-chrubuntu-tester.html has described the problem as follows:

"The only issue I have identified and isolated is an ALSA bug with internal microphone support. The internal mic is digital, and can successfully amplify and play through the laptop speakers in realtime. Setup requires typing 'alsamixer' at the command line, F5 to see all the inputs and outputs, use spacebar at Digital Capture to toggle it on and off, mute the analogue mic and turn up the digital inputs and digital boost at the far right. However, this mic input cannot be captured by any application because ALSA only feeds the analogue mic input to applications, which results in loud static. To make sure this was an ALSA bug, I uninstalled PulseAudio, but it still was present. Not sure where to go from here, and hoping the ALSA developers already are aware and working it. By the way, both ALSA Mixer and the PulseAudio speaker volume control and mute at the upper right of the Umbutu Desktop must have volume up and be unmuted."

Launchpad Janitor (janitor) wrote :

Status changed to 'Confirmed' because the bug affects multiple users.

Changed in alsa-driver (Ubuntu):
status: New → Confirmed
Charlie Dawe (integravtec53) wrote :

Raymond....I am new to Linux and tried to read up on Git, but with all the new terminology (trees, commits, etc...) I was having a hard time following. Is that link you posted above a simple thing I can download or "clone" and run a few terminal commands and have it be fixed. If so I would greatly appreciate any guidance on the subject....this bug is truly the only thing keeping me from being very happy with my Acer C7

scott (jacs102) wrote :

here is a work around . it fixed my issue
wget http://www.cisgendered.com/~keyvin/mic-fix.deb
sudo dpkg -i mic-fix.deb
sudo shutdown -r now

scott (jacs102) wrote :

dont forget to use speaker icon to increase input volume to 100%

willie (linux-author) wrote :

the 'mic-fix.deb' did the trick for me, thank you so much! i can now use skype or record clear audio using the internal mic! the 'scratchy' audio i first got when recording the fix was due to too high digital input settings in alsamixer - reducing the settings effected the fix - kudos to the author of this fix for making the C7 a fully functioning Linux boxen - w00t!

Lauren (kiahtah) wrote :

Willie, did you get a warning that said "This package is of bad quality and can harm your computer"?
This thing is my most prized possession next to my ipod touch and I don't want anything to happen to it.
But I am sick of not hearing any sound and having my mic not work when I try to skype, please get back to me ASAP.
I am very fed up.
Thanks. :D

willie (linux-author) wrote :

the mic-fix .deb merely contains an updated order/listing of modules to load - i.e., no code, just a proper kernel module insertion sequence... my alsa settings are saved under my home directory and restored when needed for proper audio thru the alsactl -f command

I cant get the mic-fix.deb, it tries to connect to the website but it says connection fails the following is what I get when I try to get the package

user@chrubuntu:~$ wget http://www.cisgendered.com/~keyvin/mic-fix.deb
--2014-07-04 19:22:24-- http://www.cisgendered.com/~keyvin/mic-fix.deb
Resolving www.cisgendered.com (www.cisgendered.com)...
Connecting to www.cisgendered.com (www.cisgendered.com)||:80... failed: Connection timed out.

venugopal (mpvenugopal2k4) wrote :

how to apply the patch mentioned above when i do not find any file named realtek.c

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.

Changed in alsa-driver (Ubuntu):
status: Confirmed → Incomplete
To post a comment you must log in.
This report contains Public information  Edit
Everyone can see this information.

Other bug subscribers