I hear a click on speakers when a sound is played, whatever the software playing it. Tha could be solved adding parameter to the kernel: snd_hda_intel.power_save=0

[Alvaro Benlloch]

As described, a click on speakers occurs when a sound is played, whatever the program playing it. Always have to be a time with no sound when a playing finishes. Searching at Fedora bugzilla, that kernel parameter was suggested. snd_hda_intel.power_save=0
I tried it and the problem is solved. I hope this helps Ubuntu solving it for overall users.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: ubiquity (not installed)
ProcVersionSignature: Ubuntu 5.4.0-65.73-generic 5.4.78
Uname: Linux 5.4.0-65-generic x86_64
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair nvidia_modeset nvidia
ApportVersion: 2.20.11-0ubuntu27.14
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: KDE
Date: Fri Jan 29 09:48:43 2021
InstallCmdLine: file=/cdrom/preseed/kubuntu.seed maybe-ubiquity initrd=/casper/initrd quiet splash --- maybe-ubiquity
InstallationDate: Installed on 2020-06-09 (233 days ago)
InstallationMedia: Kubuntu 20.04 LTS "Focal Fossa" - Release amd64 (20200423)
SourcePackage: ubiquity
Symptom: installer
UpgradeStatus: No upgrade log present (probably fresh install)

[Alvaro Benlloch (abenlloch)]

Sorry, package is PULSEAUDIO or sound system in general. I don't know how to identify the package.