The other day when I was using Linux Mint 17 on my older laptop, I found that microphone was not working properly with Skype. However, I haven’t faced similar problem while using Skype in Ubuntu 14.04.
I used this trick to fix microphone sound issue with Skype in Ubuntu 13.04, but that did not work this time. In this quick tip, I’ll share with you the fix that worked for me.
Fix microphone sound issue in Linux Mint 17
Open a terminal and use the following command:
sudo apt-get install libasound2-plugins:i386
Restart your computer if needed. The trick here is to install pulse audio plugin in 32 bit, even though I am using Linux Mint 64 bit.
I hope this quick tip helped you to fix the microphone issue for you too. Ciao
Source: Linux Mint Forums