On the laptop it's a one-touch mute button, nice and easy.
On my iPhone there is no mute button, so volume controls must be used instead, which is no problem. When I use the volume buttons when there are no media playing, it lowers my ringer volume.
The issue is that I have to wait at least until the video player loads, and depending on which video player I am using, the both volume slider is grayed out out until the video starts playing.
The combination leads to a nonzero period of time when I am exposed to the audio while I am lowering the volume.
Q: Is there a way to adjust the media volume when there is no media playing [yet]?