batte@, How to set phone volume to "Alarm only"? does this bug only repro on public transportation? I assume it should repro in office too, right?

hehe, this should reproduce everywhere. ;-)

If you use the volume rocker and decrease the volume it goes to "Alarm only" and then "Off". Maybe that's an Android N feature.

Actually "Alarms only" may be a feature that is part of the "Do not disturb" feature (Settings -> Sound -> Do not disturb). Ignore that.

New step 1 to reproduce:

1. Set phone volume to "Vibrate only" or "Silent"

Android Marshmallow and above has a Total Silence mode that will mute all audio streams (notifications, alarms and music). To use that toggle the silent mode in the quick settings and then switch to Total Silence (the top line, next to Alarms Only and Priority Only). All other modes (and pre-M) only mute the notification sounds so playing video without sound would be surprising: every other app like YouTube / Google Music / etc will use the music audio stream volume.

To achieve what you want on a system level either use the total silence mode or turn the music volume off (on L+ it's easy to do for non-current audio stream with the volume buttons - one can expand the slider popup and adjust the others).

I agree there're issues with the websites that make sounds without a clear user intent by hijacking user gestures (like scrolling) or using JS video decoders and WebAudio, but I disagree that this is the right solution.

Thanks for educating me. I would have never found these settings and thought that "Alarms only" does not mean "Alarms only". I agree that Chrome should follow Android's media stream volume that is also used by Youtube / Google Music.