[xenial] USB camera MIC: no input or high pitch until pavucontrol is opened

[Dmitry-a-durnev]

Logitech Webcam C270 connected to USB 2.0 port: no mic input or high pitch voice appears randomly during voice calls(skype test call for example). Seems? to be fixed by opening pavucontrol from Skype -> Settings -> Devices.

lsb_release -rd
Description: Ubuntu Xenial Xerus (development branch)
Release: 16.04

skype: 4.3.0.37-0ubuntu0.12.04.1

pulseaudio: 1:8.0-0ubuntu3

This also happens on ubuntu 15.10 with the same skype package version.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Vaclav Rehak (vaclav-n)]

I confirm the bug on 16.04 on Lenovo X1 Carbon (1st gen).

When I open the Sound Settings using the topbar sound icon, the Input Volume and Input Level is greyed out. Then I run "pavucontrol" and "Input Devices" tab says "No input device available".

It can be "fixed" in pavucontrol by going to Configuration tab and selecting Profile: Analog Input Stereo. It seems to stay functional until next reboot.

[Vaclav Rehak (vaclav-n)]

Forgot to mention in my comment that I am talking about the internal mic in the ThinkPad (I have no USB mic attached).

[Jaap de Haan (jaap-dehaan)]

I made a recording with pulseaudio and slowed down the speed by a factor 3 (tempo x 0,333) then on playback the sound seems to be normal.

Maybe this factor 3 is a helpful information to track down the bug for some experienced programmer in that area.

[Jaap de Haan (jaap-dehaan)]

Another important hint. I switched from a USB 3.0 to one of the few USB 2.0 ports I still have... and magically the issue disappears. Can this really be related to the use of a USB 3.0 port?