Sound+Sleep Mini White Noise Sleep Machine Works perfectly - retails for $70 Per the product information on their website: “Adaptive Sound listens to your environment and responds instantly by adjusting audio volume 48 rich and immersive non-repeating sound environments for better sleep, relaxation, and sound masking The optional sleep timer gently reduces the volume after 30, 60, 90, or 120 minutes to allow you to drift off to sleep”