[ASUS PRIME X370-PRO, Realtek ALC1220, Green Line Out, Rear] Underruns, dropouts or crackling sound

[scpatl4now]

This seems to happen at very random times. I can be listening to something and after opening another tab in the Firefox browser the sounds immediately distorts to crackling and distorted sound. The only fix is to kill the pulse audio process after pausing the audio (which continues a couple seconds after). Then restarting the audio is normal again

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: pulseaudio 1:13.99.1-1ubuntu3.12
ProcVersionSignature: Ubuntu 5.11.0-38.42~20.04.1-generic 5.11.22
Uname: Linux 5.11.0-38-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.11-0ubuntu27.21
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: scott 23106 F.... pulseaudio
 /dev/snd/controlC2: scott 23106 F.... pulseaudio
 /dev/snd/pcmC2D0p: scott 23106 F...m pulseaudio
 /dev/snd/controlC1: scott 23106 F.... pulseaudio
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Sat Oct 30 15:42:13 2021
InstallationDate: Installed on 2020-10-21 (373 days ago)
InstallationMedia: Ubuntu 20.04.1 LTS "Focal Fossa" - Release amd64 (20200731)
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: pulseaudio
Symptom: audio
Symptom_AlsaPlaybackTest: ALSA playback test through plughw:Generic successful
Symptom_Card: Family 17h (Models 00h-0fh) HD Audio Controller - HD-Audio Generic
Symptom_Jack: Green Line Out, Rear
Symptom_PulseAudioLog:

Symptom_PulsePlaybackTest: PulseAudio playback test failed
Symptom_Type: Underruns, dropouts, or "crackling" sound
Title: [System Product Name, Realtek ALC1220, Green Line Out, Rear] Underruns, dropouts or crackling sound
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 09/12/2019
dmi.bios.release: 5.13
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 5220
dmi.board.asset.tag: Default string
dmi.board.name: PRIME X370-PRO
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: Rev X.0x
dmi.chassis.asset.tag: Default string
dmi.chassis.type: 3
dmi.chassis.vendor: Default string
dmi.chassis.version: Default string
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr5220:bd09/12/2019:br5.13:svnSystemmanufacturer:pnSystemProductName:pvrSystemVersion:skuSKU:rvnASUSTeKCOMPUTERINC.:rnPRIMEX370-PRO:rvrRevX.0x:cvnDefaultstring:ct3:cvrDefaultstring:
dmi.product.family: To be filled by O.E.M.
dmi.product.name: System Product Name
dmi.product.sku: SKU
dmi.product.version: System Version
dmi.sys.vendor: System manufacturer