■ Enable the PB Sound by going to Settings → + → Behind PB Sound and/or Behind map record sound
■ To change the sound it makes, replace the res/se0/fault.wav in this line: var snd = new Audio(website + "res/se0/fault.wav"); with a sound URL, and remove the "website + " section as well.
■ For example, like this: var snd = new Audio("https://ecdldaiiere.github.io/Eddiez-Soundz/nuclearwarning.mp3");