Hello, I have been using a Shure SE115 for a few years. It is quit good. Recently, I have to do my work in noisy public areas more often. Ear plug is not effective. I am looking for a headphone/earphone that can block all the noise in a noisy environment. Any suggestion? Ideally, the device can block all these noise even without me playing the music. Is there such a device? Somebody in Apple store suggested the Bose QC20i. He said that even without turning on the music, the device has sound cancellation to remove all the noise in a noisy environment. He said that I do need to charge the device. As there is no demo in the store, I cannot verify its effectiveness. Thanks.