hi all , I'm after a bit of help if there are any electronics experts on here , my problem is my hounds barking/howling at night , I don't live on site were they are kept so I cant stop them , they are kept indoors in pens , I have tried the high pitched bark stoppers to no avail so what my plan is to fit a garden water sprinkler the rotating type above the pens plumb it in to a electric water pump but my problem is I need a sound operated switch preferably adjustable that has a built in relay so that it will switch off afer a few seconds , I have searched ebay but nothing suitable , any ideas