vent would help to an extent, though the problem will probably remain. I’ve never seen a vent cover that was very good off the store shelf, though I have figured out how to improve them. I drilled the bottom edge of the single-flap vent at my house and installed a short, 1/2-inch diameter bolt and nut on it for weight. This do-it-yourself fix keeps the flap quiet and shut, yet allows it to open when the dryer is actually running.