Mute/Unmute, how is one supposed to know the status?

[Chris Green]

I am totally bemused by "Volume Control" which I assume is actually
PulseAudio.

How is one suppsed to tell if an output is muted or not?  When I click
on the "Mute Audio" button it just changes from pale grey to dark
grey, so which is muted and which isn't muted?  Why on earth can't
words be used?

Also, on another system the Mute buttons all have a white x on a red
background and I can't get anything out of the system at all, it was
working a few days ago so how do I turn the audio output back on?

-- 
Chris Green