pulseaudio running but can't hear any sound

[Samuel Siaw]

...

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: pulseaudio 1:13.99.1-1ubuntu3.13
ProcVersionSignature: Ubuntu 5.13.0-39.44~20.04.1-generic 5.13.19
Uname: Linux 5.13.0-39-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.23
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: XFCE
Date: Sat Apr 23 00:50:09 2022
InstallationDate: Installed on 2022-04-06 (16 days ago)
InstallationMedia: Xubuntu 20.04.4 LTS "Focal Fossa" - Release amd64 (20220223)
ProcEnviron:
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: pulseaudio
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 07/25/2021
dmi.bios.release: 4.14
dmi.bios.vendor: coreboot
dmi.bios.version: MrChromebox-4.14
dmi.board.name: Banon
dmi.board.vendor: GOOGLE
dmi.board.version: 1.0
dmi.chassis.type: 9
dmi.chassis.vendor: GOOGLE
dmi.ec.firmware.release: 0.0
dmi.modalias: dmi:bvncoreboot:bvrMrChromebox-4.14:bd07/25/2021:br4.14:efr0.0:svnGOOGLE:pnBanon:pvr1.0:rvnGOOGLE:rnBanon:rvr1.0:cvnGOOGLE:ct9:cvr:sku:
dmi.product.family: Intel_Strago
dmi.product.name: Banon
dmi.product.version: 1.0
dmi.sys.vendor: GOOGLE
modified.conffile..etc.pulse.default.pa: [modified]
mtime.conffile..etc.pulse.default.pa: 2022-04-23T00:30:09.974603