Tony,

Weren't we talking about this the other night with Mike? I'd thought that when the player was running on car power, it didn't wait for a response on the serial port?

IIRC, Mike suggestion was to stick a dummy plug (or a matchstick) in the power port. Of course, if you do that, it thinks it's on home power, with all the attendant changes. (No tuner, no dimmer, 2 channels, etc.)

You'd really only want to do this while you're loading code.