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."
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