Marpac Noise Machines On Sale Today From Just $20.95! Posted on November 29, 2017 by Jeri Update: Deal over. Today only, Amazon is offering 30% off Marpac noise machines. Marpac Rohm Portable White Noise Sound Machine: $20.95 Marpac Dohm Basic All Natural Sound Machine: $20.99 Marpac Dohm-DS All-Natural Sound Machine: $30.49 Share the love: