Hi,

If you use one track (of a serial file) for your control signal then you could use a couple of tone decoders http://www.x-robotics.com/downloads/...67_SE567_2.pdf to do the job. Take two frequencies for a 0 and 1. You could even use a DTMF decoder chip like MT8870. As most audio software would let you generate DTMF tones your life would get easier. Get the trial version of Adobe Audition Pro (formerly Cool Edit Pro).