They close out a lot of external noise, however these are not noise cancelling so dont blank everything out. I thought that the cover would go all around the mattress and cover it completely. As such, I dont use the SRS function at all and the noise reduction is amazing when used with audiobooks, or even just to dampen down the ambient noise at work (I have an air conditioner that I was just used to, but these things chop it out almost entirely when in their active cancelling mode - its eerie! I was in a dark place but music brought me out of it and this thing sounds so good and is so easy to use and is so portable and lasts so long, now I start every day dancing and laughing! 3: new full-speed USB device number 7 using ehci-pci[ 9514. Being made by Kingston, chances are you arent going to have to RMA this memory. I have tried to re-calibrate the device several times and that has not worked. Great for those of us who lose our keys and phones. Suddenly they were discontinued at that store and I looked to Amazon to buy a new pair (the earpiece on one of my original sets had been smashed - I keep 2 pairs in case I forget one when I go to the gym) and noticed the were a fraction of the price I had previously paid. Ive only had it a day so time will tell as to the longevity of it but, it seems promising.