Details
Safe to run again: it sets a state, it does not toggle. The output says muted or
unmuted only after iOS confirmed it.
How: the keyboard Mute key toggles iOS full mute (all output, media in every app).
After each press SpringBoard logs the new state; the daemon reads it from the
iPhone system log over USB. If the phone was already in that state, the first press
toggles it away and a second press toggles it back (sound for about 50 ms).
The silent/ringer switch is separate: it does not silence app media.
Full mute stays on when screen capture starts or stops. Works while capture runs.
mute-unconfirmed error: the key was sent but iOS logged no change. The state is
unknown and it was not pressed again. Take a screenshot before you retry.
Not available in XCTest mode (unsupported-in-mode).