[linux-audio-dev] Silence Detection

I work with a small community radio station, and since we're continually strapped for cash we implement our studio-transmitter link by streaming audio over a network. We use a variety of players and formats (mainly xmms and realplayer), but all of them share a common problem. Despite our process monitoring software, the stream occasionally goes silent. We would like to find a way to detect when the output of the playback computer's soundcard is silent- or at least quiet enough to count as such. I was hoping that someone could give some quick hints or point me to a tutorial on writing a plugin that could live between our playback app and the sound device and monitor that stream of data. I think this would be similar to a funky visualization plugin, but so far those have all been specific to particular playback applications. I've played with ladspa (which is awesome, BTW) and I've mucked about in the internals of kde's arts but I haven't found a clean way of inserting this into the code. thanks! -Dave