[alsa-devel] Distorted audio from microphone (Logitech C310)

[Takashi Iwai]

On Tue, 16 May 2017 07:58:43 +0200,
Greg KH wrote:
> 
> On Mon, May 15, 2017 at 03:29:09PM +0200, Domker_ wrote:
> > My webcam Logitech C310 have a distored microphone audio on kernel 4.10.15-1
> > and 4.11.0-1. (on 4.9.27-1 and the older ones is fine).
> > The distortion effect is as if I spoke very, very fast (like a damn Mickey
> > Mouse)
> > 
> > I checked and the bug occurs on both computers I have. (with the same
> > camera/different sound cards, hardware and different Linux distributions)
> > The bug always occurs when running a system with a kernel newer than 4.9.x.
> > 
> > The camera has two internal microphones.
> > Secound kernel 4.11.0-1 (x86_64) compiled from kernel.org!
> > 
> > (tested under Linux Arch and Linux Manjaro)
> 
> Hm, maybe the Linux sound developers can help out here (added to cc:)

Through a quick look, there only a few commits between 4.9.27 and
4.10.15 regarding USB-audio.  The suspicious one is

commit fd1a5059610cd3887f1050171a840ca864108730
    ALSA: usb-audio: more tolerant packetsize

Could you try to revert this?


thanks,

Takashi