When you have opened AudioRelay, you might have see a error. that's beacause you are missing a some fonts on your system. Install the give below fonts on your system.
sudo pacman -S ttf-dejavu-nerd
sudo pacman -S noto-fonts
After Opening AudioRelay
Install sudo pacman -S pavucontrol
Set AudioRelay Speaker to Deafult instead of Built-in Audio Analog Stereo Speakers.
Your pavucontrol GUI should match as provided below
