No sound on wake, Dummy Output always takes over. 'pulseaudio -k' the fix

It be caused by a new kernel introduced in 19.10 like this case:

• Lagging after update to 19.10 from 19.04

If not then you can use this script /etc/systemd/system-sleep/reloadpulse:

#!/bin/sh

# NAME: reloadpulse
# PATH: /lib/systemd/system-sleep
# CALL: Called from SystemD automatically

# DESC: PulseAudo 8 sets sound to dummy ouput when going to sleep.
#       This script kills and reloads pulse audio.

# DATE: November 25, 2019.

# NOTE: Written for ask ubuntu question:
#       https://askubuntu.com/questions/1191649/why-no-sound-on-wake-dummy-output-takes-over-pulseaudio-k-the-fix

case $1/$2 in
  pre/*)
    echo "$0: Going to $2..."
    ;;
  post/*)
    echo "$0: Waking up from $2..."
    pulseaudio -k
    ;;
esac

Mark the script executable with chmod a+x /etc/systemd/system-sleep/reloadpulse

After updates deactivate it with chmod a-x /etc/systemd/system-sleep/reloadpulse

Then if the update didn't fix the problem make it executable again.

You need to reboot for changes to take effect.

I have a similar problem with Ubuntu 20.04.

This command solved the problem: pulseaudio --start