cronjob set for the timed events
Using Alsa amixer (they say it can be done also with pulse).
This is redundant to Airtime and if you search the forum for my post on Airtime line input ,You can find something to work with.
The info from the wiki you post above was written for a silence in airtime ,you will get a better understanding of that wiki ,if you look here in the hack section http://forum.sourcefabric.org/discussion/15701/fallover-101-how-to-make-all-scripts-worked-easy-steps-to-build-your-scripts-fixed-silence.
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