Set pulseaudio default sink to the next available sink and move all existing sink-inputs to the new default. Wraps around once the last input is reached.

pulseaudio-next-sink.sh

#!/bin/sh

# Set pulseaudio default sink to the next available sink and move all existing sink-inputs to the new default. 
# Wraps around once the last available sink is reached.
# 
# (C) 2022, @j2L4e
# MIT License

currentline=$(pactl list short sinks | grep -n "$(pactl get-default-sink)" | cut -d: -f 1)
lastline=$(pactl list short sinks | wc -l)
nextline=$(($currentline % $lastline + 1))
nextsink=$(pactl list short sinks | head "-n$nextline" | tail -1 | cut -f 1)

pactl set-default-sink "$nextsink"

for sinkinput in $(pactl list short sink-inputs | cut -f 1); do
  pactl move-sink-input "$sinkinput" "@DEFAULT_SINK@"
done