I get this issue consistently when running Firefox. Not so much
chromium, but still sometimes.
I don't know what Firefox is doing vs. chromium to have such a
significantly different impact
on audio. Often times when the issue pops back up, I restart the browser
and get many hours
more of having the clicking to a lesser degree. I must say though,
although OpenBSD quite
noticeably has this issue, I have recently found out that Linux also has
this issue to some degree.
Courtney
On 6/10/25 4:08 AM, Claudio Jeker wrote:
On Tue, Jun 10, 2025 at 12:05:24PM +0200, Alexandre Ratchov wrote:
On Mon, Jun 09, 2025 at 12:29:09AM +0100, Chris Narkiewicz wrote:
I have a pair of wireless headphones with USB dongle.
When connected, device is attached as uaudio0.
I noticed frequent clicks when playing music and browsing web.
I adjusted sndiod buffer size and number of frames, but no result.
The clicking is probably caused by the browser "stealing" the CPU from
sndiod and/or from the usb driver. This can't be fixed by increasing
the audio buffer size; the default one is already huge, btw.
AFAIK the USB audio code still uses KERNEL_LOCK so anything doing heavy
disk operations will cause noticable clicking.
I normally notice it with git commands that just hammer the kernel and
spin on KERNEL_LOCK for no good reason.
I noticed that play.errors parameter is rising during clicking,
suggesting buffer underruns:
# audioctl -f /dev/audioctl1
audioctl -f /dev/audioctl1
name=uaudio0
mode=play,record
pause=0
active=1
nblks=2
blksz=1020
rate=48000
encoding=s24le3
play.channels=2
play.bytes=2784600
play.errors=12240
record.channels=1
record.bytes=1392300
record.errors=0
I tried to adjust the nblks and blksz to larger values:
# audioctl -f /dev/audioctl1 blksz=8192 nblks=16
audioctl -f /dev/audioctl1 blksz=8192 nblks=16
nblks: 2 -> 16
blksz: 1020 -> 8192
To change the hardware parameters, use "-f /dev/audio1", but
see below.
So far, so good - I thought.
When starting mpv (or mpd), the value is reset to
nblks: 2
blksz: 1020
and clicking continues.
Why the value is accepted initially only to be reverted when I start
playing sound?
The program using the device (sndiod in your case) sets its own
parameters, so they change as soon as the program starts using the
device.
To change the parameters, configure the program. Ex, for sndiod:
rcctl set sndiod flags -z 480 -b 960
