[bcm2835_hdmi - bcm2835 HDMI 1, playback] No sound at all

[Mike Hall]

Running Ubuntu Mate 20.04 on Raspberry Pi 4 with Dual Monitor Set-up

Description: Ubuntu 20.04.1 LTS
Release: 20.04
Packages involved: Unknown

Issue: I can choose either 2 HDMI monitors or sound but not both
Expected: Sound works with both monitors plugged in

(1) No sound from headphone jack or HDMI in two monitor configuration
(2) If I unplug 2nd monitor and reboot, sound works fine in HDMI or headphone jack
(3) If I plug in second monitor while Pi is running, no picture in second monitor but sound still works
(4) Sound works normally in Raspbian

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: alsa-base 1.0.25+dfsg-0ubuntu5
ProcVersionSignature: Ubuntu 5.4.0-1025.28-raspi 5.4.73
Uname: Linux 5.4.0-1025-raspi aarch64
ApportVersion: 2.20.11-0ubuntu27.14
Architecture: arm64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC2: loreleiandmike 1211 F.... pulseaudio
 /dev/snd/pcmC2D0p: loreleiandmike 1211 F...m pulseaudio
CasperMD5CheckResult: skip
CurrentDesktop: MATE
Date: Wed Jan 6 19:45:47 2021
ImageMediaBuild: 20200812
PackageArchitecture: all
ProcEnviron:
 LANGUAGE=en_US
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: alsa-driver
Symptom: audio
Symptom_AlsaPlaybackTest: ALSA playback test through plughw:b1 failed
Symptom_Card: Built-in Audio - bcm2835 Headphones
Symptom_DevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC2: loreleiandmike 1211 F.... pulseaudio
Symptom_Type: No sound at all
Title: [bcm2835_hdmi - bcm2835 HDMI 1, playback] No sound at all
UpgradeStatus: No upgrade log present (probably fresh install)