This was also affecting me, causing very loud hissing on Skype calls. The change in https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/1085402/comments/6 fixes it for me, that is, in /usr/share/pulseaudio/alsa-mixer/paths /analog-input-mic.conf in the "[Element Mic Boost]" section, change "volume = merge" to "volume = zero" and restart Pulseaudio ("sudo pkill pulseaudio") then restart Skype.
I also had to manually set the Mic Boost values to zero in alsamixer (F6, change card, "HDA Intel PCH"). -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1085402 Title: PulseAudio overuses 'Boost' control of microphone input producing bad audio quality To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/1085402/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs