Same here. Already one trip to the comcast store to get a new one and the second box is even noisier. Planning on going back again this weekend for a third try but will plug in at the store before I take it home. We upgraded our internet to gigabit and Comcast made us swap our standard, silent cable box with a larger, uglier DVR box (a feature we will never use) that now emits a constant humming sound which fills our living room. Beware the unwanted upgrade!
Does your DVR have the shape above with on green LED on the front bottom middle, no clock?