Two possible sounds output, when playing movie from youtube, output is set to wrong one automatically after 5 seconds [, Realtek ALC283, Black Headphone Out, Left] fails after a while

I start playing movie in Firefox and there is no sound coming out. I open sound configuration and change
"Output Device" from "HDMI / DispalyPort - Built in Audio" to "Headphones - Built in Audio"

Sound starts to play and then after 5 seconds it stops again.

When I open sound configuration again, I can change "Output Device" again and sound plays again for 5 seconds and then it is turned off.

I play sound using my display built in device connected through HDMI cable and also using audio cable. Sound is not working through HDMI cable. It is working using audio cable or headphones.

My expectation is, when I set output device to be audio cable - it will not be changed to HDMI cable.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: alsa-base 1.0.25+dfsg-0ubuntu5
ProcVersionSignature: Ubuntu 5.4.0-18.22-generic 5.4.24
Uname: Linux 5.4.0-18-generic x86_64
ApportVersion: 2.20.11-0ubuntu20
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: lmlich 1369 F.... pulseaudio
 /dev/snd/pcmC1D0c: lmlich 1369 F...m pulseaudio
 /dev/snd/pcmC1D0p: lmlich 1369 F...m pulseaudio
 /dev/snd/controlC0: lmlich 1369 F.... pulseaudio
CurrentDesktop: ubuntu:GNOME
Date: Wed Mar 18 21:09:40 2020
InstallationDate: Installed on 2019-12-27 (82 days ago)
InstallationMedia: Ubuntu 20.04 LTS "Focal Fossa" - Alpha amd64 (20191223)
PackageArchitecture: all
SourcePackage: alsa-driver
Symptom: audio
Symptom_Card: Built-in Audio - HDA Intel PCH
Symptom_Jack: Black Headphone Out, Left
Symptom_PulseAudioLog:
 bře 18 21:02:14 lmquiet dbus-daemon[770]: [system] Activating via systemd: service name='org.freedesktop.RealtimeKit1' unit='rtkit-daemon.service' requested by ':1.42' (uid=125 pid=979 comm="/usr/bin/pulseaudio --daemonize=no " label="unconfined")
 bře 18 21:02:31 lmquiet systemd[972]: pulseaudio.service: Succeeded.
 bře 18 21:02:42 lmquiet systemd[972]: pulseaudio.socket: Succeeded.
Symptom_Type: Sound works for a while, then breaks
Title: [, Realtek ALC283, Black Headphone Out, Left] fails after a while
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 01/20/2016
dmi.bios.vendor: Intel Corporation
dmi.bios.version: RYBDWi35.86A.0354.2016.0120.0912
dmi.board.name: NUC5i3RYB
dmi.board.vendor: Intel Corporation
dmi.board.version: H41000-503
dmi.chassis.type: 3
dmi.modalias: dmi:bvnIntelCorporation:bvrRYBDWi35.86A.0354.2016.0120.0912:bd01/20/2016:svn:pn:pvr:rvnIntelCorporation:rnNUC5i3RYB:rvrH41000-503:cvn:ct3:cvr: