It’s strange sometimes how things that should be simple can start to seem very complicated. A case in point is Skype on Kim’s Acer Aspire One. I have Skype working very well on my laptop, but after installing it on Kim’s, the microphone didn’t seem to be working at all!

Obviously, I’d followed my own advice in a previous post. I also confirmed that the microphone was working in Sound Recorder, but when I made a Skype test call, the conversation was very one-sided indeed.

A lot of digging around showed that PulseAudio treats everything as stereo – even if the microphone is mono! The two inputs cancel each other out, resulting in a stony silence for whoever you’re trying to talk to on Skype.

The solution is as follows:

• Go to System -> Administration -> Synaptic Package Manger
• Search for, and install the pavucontrol package
• Go to Applications -> Sound  & Video -> PulseAudio Volume Control
• Click on the little padlock icon to unlock the channels so that you can adjust the left and right channels individually – normally they’re locked together. It is a padlock icon on my machine; however on Kim’s netbook it looked more like a little grey shield.
• Now drag the one of the channels down to about 10% and the other one to about 80%. You should immediately see activity in the sound sensor bar beneath the channels.
• Close the Volume Control and try a Skype test call again. You may need to adjust the levels a bit – my first settings were picking up too much ambient noise, the above values worked for me, but YMMV.

So now Kim can use Skype on the netbook. A simple solution, but I’d never have guessed that a stereo/mono conflict was the cause. On my laptop, I have a stereo microphone with two little holes either side of the webcam. On Kim’s there’s just one hole and it’s obviously just a mono mike. Hope this helps anyone who’s having the same problem.

Sources: https://help.ubuntu.com/community/Skype