pulseaudio / alc1220 sound clicks interruptions etc

Hello world :-)

I just switched to Intel Ultra 9 285K platform with ASUS mainboard
which has currently very popular Realtek ALC1220 HDA sound codec. In
theory this codec supports 32-bit sound with 192kHz samplerate
playback (and some lower params for recording).

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?

Any hints welcome :-)
Tomek

-- 
CeDeROM, SQ7MHZ, http://www.tomek.cedro.info