PulseAudio freezes applications when sound is required

Question

So I have a major problem with PulseAudio. When any app play sound (from a media player to a system sound, and even the volume change sound or a virtual machine through VirtualBox), it makes the app freeze for 10 seconds and play the sound.

It happens only if no sound played since a short time (if I listen to music there is no freezes for any app) and it's very annoying...

Here's what I already tried:

1. Rebooting, of course, because reboot fix most problems, but not mine...
2. sudo apt install pulseaudio-module-jack and insert this into /etc/pulse/default.pa:

load-module module-jack-sink
load-module module-jack-source

3. Uninstall (sudo apt purge --auto-remove pulseaudio* alsa*) and reinstall PulseAudio (and ALSA and everything related)
   • I don't have this problem if I uninstall PulseAudio
4. Checking system logs (/var/log/syslog) → nothing related to PulseAudio or ALSA
5. Tried to play through mplayer or another command-line audio player. The problem is still there and no error message.

I finally gave up, waiting for a solution, or switching back to Windows if the problem persists (because I do a lot of audio-related things so it's major for me). Searching on Internet didn't help, it seems like nobody have the (exact) same problem... Note that the sound was perfectly working 1 week ago (and when I tested the beta of Ubuntu 20.04), and I didn't changed something sound-related.

If this may help, I installed other desktops on my system (Xfce and a not-fully uninstalled KDE) which may conflict with PulseAudio.

I hope there is a solution that don't need me to reinstall everything, it's the last thing I will do if I don't have a solution.

Regards.

Answer 1

After a bit research, I was running a lowlatency kernel (which I manually installed). Switching back to a generic kernel fixed the problem.

If you manually installed a lowlatency (or another) kernel, you can use GRUB recovery options to start a specific kernel:

• If you see the GRUB menu when you boot, just select « Advanced options for Ubuntu » and select a generic kernel.
• If you don't see the GRUB menu when you boot normally, press Esc at the early boot process (between POST [the end of hardware initialization process] and real system boot). This will open the GRUB menu, where you can select « Advanced options for Ubuntu » and boot a generic kernel.