I am confused with your answer to my question, as I am not really technically minded
see below output of my "/etc/init.d/tvheadend":
sudo cat /etc/init.d/tvheadend
#############################################################
#! /bin/sh
### BEGIN INIT INFO
# Provides:          tvheadend
# Required-Start:    $local_fs $remote_fs udev
# Required-Stop:     $local_fs $remote_fs
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
### END INIT INFO
# Author: Andreas Ă–man
# Do NOT "set -e"
# PATH should only include /usr/* if it runs after the mountnfs.sh script
PATH=/usr/sbin:/usr/bin:/sbin:/bin
DESC="Tvheadend"
NAME=tvheadend
DAEMON=/usr/bin/$NAME
PIDFILE=/var/run/$NAME.pid
SCRIPTNAME=/etc/init.d/$NAME
# Exit if the package is not installed
[ -x "$DAEMON" ] || exit 0
# Read configuration variable file if it is present
[ -r /etc/default/$NAME ] && . /etc/default/$NAME
# Configure command line options
[ "$TVH_ENABLED" = "1" ] || exit 0
ARGS="-f"
[ -z "$TVH_USER"      ] || ARGS="$ARGS -u $TVH_USER"
[ -z "$TVH_GROUP"     ] || ARGS="$ARGS -g $TVH_GROUP"
[ -z "$TVH_CONF_DIR"  ] || ARGS="$ARGS -c $TVH_CONF_DIR"
[ -z "$TVH_ADAPTERS"  ] || ARGS="$ARGS -a $TVH_ADAPTERS"
[ "$TVH_IPV6" = "1"   ] && ARGS="$ARGS -6"
[ -z "$TVH_HTTP_PORT" ] || ARGS="$ARGS --http_port $TVH_HTTP_PORT"
[ -z "$TVH_HTTP_ROOT" ] || ARGS="$ARGS --http_root $TVH_HTTP_ROOT"
[ -z "$TVH_HTSP_PORT" ] || ARGS="$ARGS --htsp_port $TVH_HTSP_PORT"
[ -z "$TVH_ARGS"      ] || ARGS="$ARGS $TVH_ARGS"
[ "$TVH_DEBUG" = "1"  ] && ARGS="$ARGS -s"
# Load the VERBOSE setting and other rcS variables
[ -f /etc/default/rcS ] && . /etc/default/rcS
# Define LSB log_* functions.
# Depend on lsb-base (>= 3.0-6) to ensure that this file is present.
. /lib/lsb/init-functions
#
# Function that starts the daemon/service
#
do_start()
{
	# Return
	#   0 if daemon has been started
	#   1 if daemon was already running
	#   2 if daemon could not be started
        udevadm settle
	start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON --test > /dev/null \
		|| return 1
	start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON -- \
		$ARGS \
		|| return 2
}
#
# Function that stops the daemon/service
#
do_stop()
{
	# Return
	#   0 if daemon has been stopped
	#   1 if daemon was already stopped
	#   2 if daemon could not be stopped
	#   other if a failure occurred
	start-stop-daemon --stop --quiet --retry=TERM/30/KILL/5 --pidfile $PIDFILE --name $NAME
	RETVAL="$?"
	[ "$RETVAL" = 2 ] && return 2
	# Many daemons don't delete their pidfiles when they exit.
	rm -f $PIDFILE
	return "$RETVAL"
}
case "$1" in
  start)
	[ "$VERBOSE" != no ] && log_daemon_msg "Starting $DESC" "$NAME"
	do_start
	case "$?" in
		0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
		2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
	esac
	;;
  stop)
	[ "$VERBOSE" != no ] && log_daemon_msg "Stopping $DESC" "$NAME"
	do_stop
	case "$?" in
		0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
		2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
	esac
	;;
  restart|force-reload)
	#
	# If the "reload" option is implemented then remove the
	# 'force-reload' alias
	#
	log_daemon_msg "Restarting $DESC" "$NAME"
	do_stop
	case "$?" in
	  0|1)
		do_start
		case "$?" in
			0) log_end_msg 0 ;;
			1) log_end_msg 1 ;; # Old process is still running
			*) log_end_msg 1 ;; # Failed to start
		esac
		;;
	 
)
	  	# Failed to stop
		log_end_msg 1
		;;
	esac
	;;
  status)
        status_of_proc -p $PIDFILE $DAEMON $NAME && exit 0 || exit $?
        ;;
  )
	echo "Usage: $SCRIPTNAME {start|stop|restart|force-reload}" >&2
	exit 3
	;;
esac
:
#############################################################
And it looks like IPv6 is enabled but TVHeadEnd is ignoring it ...
Or is it somewhere else I need to set the -6 parameter?
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