Having just had my empeg installed in my new car, I've got some interest in something like this. A few questions...

1. You mentioned you were having problems with engine noise inducing a false start, is that still the case?
2. If I understand right, it switches over as soon as it senses audio, and then waits for a period of silence before switching back. How variable is this time period between switching back?
3. Is it possible to tell it never to switch back? i.e. always switch when it gets sound, but wait for the user to manually switch back to Aux.
4. Once you have something reasonably finalized, would you consider building them and selling them? It doesn't look *too* complicated, but I'm not sure I'd want it to be my first electronics project, either.