NX Sentry 0.2.2

Sound check — a new button in the Alarm panel.

An alarm you cannot hear is this app's worst failure and was its most invisible
one: a suspended audio engine, a graph producing no signal, and sound going to a
device you are not listening to all run the code perfectly and look identical to
a working sentry.

Sound check plays one bar, taps the master with an analyser to measure what
actually left the audio graph, and tells you which of those three it is and what
to do next. The audio engine is also warmed on the first click or key press in
the window, so it can never sit suspended until the first alarm needs it, and an
alarm that fires while the engine cannot sound now says so rather than flashing
an amber banner over silence.