Recently bought the Bose 700 headphones and loved it before the latest firmware update. Others have mentioned buzzing and glitch noises that I also experience when connecting to multiple devices which I won't discuss here but I also experience a high bitched vibration noise that only occurs on the left side speaker. This may not be related to the firmware update but a physical defect. Only occurs occasionally, not continuous. If I am wearing the headphones, seems to occur for higher frequencies rather than lower end ranges.