Re: pulseaudio / alc1220 sound clicks interruptions etc

Tomek CEDRO wrote:
> Hello world :-)
> 
> I am experiencing really annoying sound clicks and glitches /
> interruptions on FreeBSD that are hard to stand when using anything
> beyond 16-bit 44.1kHz sound. At 48kHz glitches are rare but already
> show up, at 96 and 192kHz sound is unusable. No problems like this on
> windoze.There is one USB audio card (KM-BT1) that allows me to connect
> over bluetooth headphones and it has the same issues.
> 
> I played around with almost all systctl settings latency buffers
> vchans bitperfects uadio params etc. It did not happen on the old
> hardware. I am running Enlightenment wit PulseAudio backend. PCI-e
> nvidia GTX1060 GPU. 14.2-RELEASE AMD64.
> 
> Most likely PulseAudio is to blame as it also does some conversions on
> the fly and may not catch up. Also played with most of the PA
> daemon.conf settings with no good results, also in tandem with pcm
> sysctl settings. When vchanmode is set to adaptive then PA
> reconfrigures audio device to 16/44.1. When vchanmode is fixed and
> both params of pcm and pa are the same glitches are unbearable and
> their intensity corelates with applications use (i.e. switching
> windows distrubs sound etc).
> 
> Are there any limitations for 24/32-bit audio and samplerate over
> 44.1kHz o n FreeBSD?
> 
> Are there any tunables that may help OSS / PulseAudio run smoother?
> 
> Are these known issues of ALC1220 sound codec?
> 
> Should I run PulseAudio as system service so it gets realtime / nice
> access? If so how to make it secure as there is no rc script for that?

I cannot really see a clear pattern here, but I think we can try to
narrow down the issue. What is the behavior if you use _only_ plain OSS?
No pulseaudio, ALSA, virtual_oss, etc.

Also, do you vchanrate for both recording and playback? If not, that
could be an issue as well (see BUGS section in sound(4)'s man page [1]).

Christos

[1] https://man.freebsd.org/cgi/man.cgi?query=sound&apropos=0&sektion=0&manpath=FreeBSD+15.0-CURRENT&arch=default&format=html