@Adam159I don't have a 700 but I have a QC35ii. I can tell you that for a QC35ii, if it doesn't get audio for a specific time period, it will turn itself off. You can specify in the Bose Connect app what the interval is. I am not aware of any other feature in Connect to turn off the headphone after a period of time (even if the audio is playing). So unless I missed something, you would need to have an app on your phone or application on your computer that is in the business of playing audio and has a sleep timer as well. Then when the app/application stops playing at a particular time, the QC35 will turn itself off after the time you specified in the Connect app.