Request: Silence Detection

Addon or Feature Request - Silence Detection

I would really like to have an Addon that allows me to set:
Silence Level
Duration of Silence
Email Address
Email Message (one line)
(Possibly) Alternate Stream

I know this is a Pro type feature, but it sure would make my day.
And every terrestrial & internet radio geek would have a PiMusicBox to monitor every stream.