Sound crackling – Ubuntu 22.04

Question

I have sound disturbances: A quiet crackling in the background and a loud hissing / crackling when I start Firefox, for example.

The problem occurs only when playing through the speakers – the speakers are connected directly via AUX and are powered via USB.  The speakers are not the problem; these disturbances do not occur under Windows.

What I've tried so far

1. in config: /etc/pulse/default.pa:

   • Added tsched=0 to the line load-module module-udev-detect && pulseaudio -k
   • Commented out the following line: load-module module-suspend-on-idle && pulseaudio -k

2. in config /etc/pulse/daemon.conf:

   • Set Pulse default-sample-rate to 48000 && pulseaudio -k

3. killall pulseaudio

4. Unplugged the speakers and plugged them in again

System information:

• Linux system 5.15.0-33-generic #34-Ubuntu SMP Wed May 18 13:34:26 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux
• Ubuntu 22.04 LTS
• ii pulseaudio 1:15.99.1+dfsg1-1ubuntu1 amd64 PulseAudio sound server

Answer 1

On my system this seems to have been caused by the volume change deferred volume setting in /etc/pulse/daemon.conf. When I set enabled-deferred-volume = no and made sure my lines for default-sample-rate and alternate-sample-rate were commented out, my crackling went away after I rebooted pulseaudio pulseaudio -k && pulseaudio --start

Edit: the issue ended up returning when I slept and unslept my system. I'm not sure why but the sample rate changed from 44100Hz to 48000Hz when my system restarted and when it was at 48000Hz the crackling came back. So I uncommented the default-sample-rate and set it to 44100. My headphones show up in several different output modes so to see which sample mode was working with and without the crackling I checked pacmd list-sinks | grep "sample spec" -B 12 which showed "state: RUNNING" on the one I wanted to check and the sample spec for the output frequency at the bottom.

Answer 2

Playback was pausing intermittently so I dropped default-sample-rate to 20000 (arbitrarily)in /etc/pulse/daemon.conf and it seems to have solved the problem.

Answer 3

I had a similar issue in my desktop setup, a lot of intermittent but then persistent hissing and crackling. Rebooting helped about 50% of the time, and sometimes restarting pulseaudio. Finally figured out that system grounding was my problem. I had inadvertently created a ground loop between the system housing, UPS, and sound system (Logitech subwoofer).

Answer 4

I have tried many ways but ultimately found the solution like this:

ı have installed alsamixer:

sudo apt update
sudo apt install alsa-utils

Then open alsamixer by alsamixer command. The screen will open in the terminal. click f6 and select your device, then scroll right via the right arrow and come to Auto-mute mode. You can follow it by checking the item option above. you need to enable it by pressing the up arrow key. Eventually, it will suddenly stop popping sound. I wish you good work :)

Answer 5

On my end I have never been able to fix the problem for good. These days, when this happens, I just do:

pulseaudio -k

And launch again whatever audio source was playing. Every single time, the sound is clean up to the next sleep or reboot. Not a real solution but I hope it helps some.