Make microphone work with Aspire one 522 and 722

External microphone: works fine with Ubuntu 12.04.

Internal microphone: needs manual configuration with older kernels, as follows.
With kernel 3.6 and later, everything should work without any extra setup

* Open a terminal window and run "alsamixer"
* press F6 and choose "1 HDA ATI SB" as a sound card to configure by pressing Enter
* to see the mic-related sliders, press F5 and move the cursor keys to the right, only the outermost three sliders need to be set to a level of 56 by pressing the Up key
* then, by pressing the "c" key on each of the three sliders, the volume level of each right channel needs to be put to 0
* finally, quit alsamixer by pressing ESC.

Relevant threads on Ubuntu forums:
* Acer Aspire One AO722 Microphone Not Working Ubuntu 12.04LTS