Set the default sink and source

make-it-sound.sh

#!/bin/bash

DEFAULT_CARD=alsa_card.pci-0000_01_00.1
DEFAULT_SOURCE=alsa_input.usb-046d_HD_Pro_Webcam_C920_B6E53ECF-02.analog-stereo

SOUND_FILE=ChID-BLITS-EBU-Narration441-16b.wav

function stop_sound_system() {
    echo "Stopping pulseaudion"; killall pulseaudio
    echo "Waiting 10s ..."; sleep 10
}

function set_default_sink() {
    # extract current output
    local active_output
    local profile
    local sink

    active_output=$(pactl list | grep hdmi-output \
        | grep -v 'not available' \
        | grep 'available' \
        | egrep -o 'hdmi-output-[^:]+' \
        | uniq)

    # sink looks like 
    #   alsa_output.pci-0000_01_00.1.hdmi-stereo
    # which means it can be build based on the CARD value
    if [[ "$active_output" = "hdmi-output-0" ]]; then
        profile="output:hdmi-stereo"
        sink="${DEFAULT_CARD/card/output}.hdmi-stereo"
    elif [[ "$active_output" = "hdmi-output-1" ]]; then
        profile="output:hdmi-stereo-extra1"
        sink="${DEFAULT_CARD/card/output}.hdmi-stereo-extra1"
    else
        echo "Unknown active output: $active_output"
        exit 1
    fi

    pactl set-sink-mute "${sink}" 0
    pactl set-sink-volume "${sink}" 50%

    pactl set-card-profile "${DEFAULT_CARD}" "${profile}"
    pactl set-default-sink "${sink}"

    pactl set-default-source "${DEFAULT_SOURCE}"
}

set_default_sink

play "$SOUND_FILE" > /dev/null 2>&1 &
while true; do
    read -p "Do you hear a sound? (y/n) " yn
    case $yn in
        [Yy]* ) kill $!; echo "All fine."; exit 0;;
        [Nn]* ) kill $!; stop_sound_system; set_default_sink; break;;
        * ) echo "Please answer y or n." ;;
    esac
done

while true; do
    read -p "Checking sound again. Do you hear a sound? (y/n) " yn
    case $yn in
        [Yy]* ) kill $!; echo "All fine."; exit 0;;
        [Nn]* ) kill $!; echo "Please troubleshoot problem."; exit 0;;
        * ) echo "Please answer y or n." ;;
    esac
done