I've got a Lenovo B50-70 , it has Ubuntu 14.04.1 os . I downloaded skype but can't make the microphone work on it.I already tried most of the solutions I found on the web and nothing worked.
Please some help
Install PulseAudio Volume Control
(pavucontrol), unlock the left and right input channels, set one channel to 0%, don't allow Skype
adjust the mixer levels.
It reduced the problem in my installation (Microphone works well with Audacity, but not with Skype).
Seems to be a problem with a ALC283.