Shell script to make jackd and pulseaudio (and optionally fluidsynth) coexist with minimal interruption to my youtubing. Also it Works For Me™ on my laptop, will keep working on it

audio

#!/bin/bash

###
# Script to launch jackd and reroute PulseAudio through it. And optionally
# start fluidsynth.
#
# READ THE NOTES PLEASE

###
# Usage (assuming this script is named `audio`, is in your PATH, and is
# executable):
#
#   audio {start|stop} DEVICE [-f]
#
#     start     Starts up jack and configures PulseAudio to route sound through
#               it.
#
#     stop      Terminates jack and restores PulseAudio's original behavior. If
#               fluidsynth is running, it is terminated as well.
#
#     DEVICE    Format "C,D", for a card number C and a device number D.
#               See the NOTES section for details.
#
#     -f        (Optional) Start fluidsynth along with jack.

###
# NOTES
#
# 1. You'll need a package that on most distros is called `pulseaudio-jack`. It
# contains PulseAudio / jackd interop modules. Just install it and this script
# does everything else.
#
# 2. There's an argument defined below called DEVICE. You need to make sure it
# contains the identifier of the sound card and sound device you want to use.
#
# To figure that out it's super duper simple. If you have `aplay` run this:
#
#   aplay -l
#
# Find the card you want, eg
#
#   card 1: PCH [HDA Intel PCH], device 0: ALC3232 Analog [ALC3232 Analog]
#     Subdevices: 1/1
#     Subdevice #0: subdevice #0
#
# This entry says card 1 and device 0, so I run this script as
#
#   $> audio start "1,0"
#
#
# (If you don't have `aplay` install the `alsa-utils` package for your distro.)
#
# 3. You may need to refresh any browser tabs or restart any applications using
# the sound card when you run `audio start`.

###
# Credit for the initial script goes Ted Felix
#   (see http://tedfelix.com/linux/linux-midi.html)
#
# Additional credit goes to this Arch Linux Wiki page:
#   https://wiki.archlinux.org/index.php/PulseAudio/Examples

DEVICE="$2"

if [ -z "${DEVICE}" ];
then
    echo "Please select a device (formatted, eg '1,0' for card 1, dev 0)."
    exit 1
fi

case $1 in

    start )
        if pgrep jackd
        then
            echo jackd is already running
        else
            # tell pulse to suspend for a bit
            pacmd suspend true

            pasuspender -- jackd -d alsa --device hw:$DEVICE \
                &>/tmp/jackd.out &

            sleep .5

            # tell pulse to load the jack modules
            pactl load-module module-jack-sink channels=2
            pactl load-module module-jack-source channels=2
            pacmd set-default-sink jack_out
            pacmd set-default-source jack_in

            if pgrep jackd
            then
              echo jackd is running
            else
              echo There was a problem starting jackd.
              exit 1
            fi
        fi

        # If fluidsynth is installed then start it as well
        if [ "$3" = "-f" ] && hash fluidsynth 2>/dev/null; then
            # Start fluidsynth
            fluidsynth --server --no-shell --audio-driver=jack \
                --connect-jack-outputs --reverb=0 --chorus=0 --gain=0.8 \
                /usr/share/soundfonts/FluidR3_GM2-2.sf2 \
                &>/tmp/fluidsynth.out &

            sleep 1

            if pgrep fluidsynth
            then
                echo fluidsynth is running
            else
                echo There was a problem starting fluidsynth.
            fi
        fi

        ;;

    stop )

        # fluidsynth may not be installed
        if pgrep fluidsynth
        then
            killall fluidsynth
        fi

        if pgrep jackd
        then
            # unload the pulse jack modules
            SINKID=$(pactl list | grep -B 1 "Name: module-jack-sink" | \
                grep Module | sed 's/[^0-9]//g')
            SOURCEID=$(pactl list | grep -B 1 "Name: module-jack-source" | \
                grep Module | sed 's/[^0-9]//g')
            pactl unload-module $SINKID
            pactl unload-module $SOURCEID
            pactl load-module module-suspend-on-idle
            pasuspender -- sleep 5

            killall jackd
        fi

        # unsuspend pulse
        pacmd suspend false

        echo Audio servers stopped.
        ;;

    * )
        echo Please specify start or stop...
        ;;
esac