On Tue, Apr 10, 2018 at 03:20:33PM +0200, Robert Klein wrote:
> Hi Daniel,
> 
> On Wed, 4 Apr 2018 03:22:04 -0300
> Daniel Bolgheroni <dan...@bolgh.eng.br> wrote:
> 
> > Hi,
> > 
> > audio is stuttering on media playback when run through sndiod. It's OK
> > without it.
> 
> Maybe related.  Yesterday I disabled webcam and microphone in BIOS on
> my X250.  Then Video playback (audio and video) was stuttering. I
> didn't investigate further, as: reverting BIOS settings made it Ok
> again.

Thanks. Few notes for the mailing-list archives:

Certains laptops have a "disable microphone" knob in the BIOS which
makes the device operate play-only, but it still reports full-duplex
capability. This confuses any full-duplex program, including sndiod,
and makes sound stutter. I've found no way to detect this situation.

Until we manage to properly detect it in the azalia driver, I'd
suggest not using the BIOS knob (ie keep your microphone enabled). To
disable it, run as root:

        chmod 600 /dev/audio[0-9]

and restart audio programs (or reboot if unsure). This is reliable
because sndiod has no root privileges; even if it is compromised, the
attacker won't be able to record. And this works for everyone, even
for those without the BIOS "feature" :-)

HTH

Reply via email to