When dealing with some parts used in car audio, the suppliers are simply not used to dealing with anyone smaller than (eg) Blaupunkt, Sony, Pioneer, etc. They look at you like you're mad, and simple things like getting databooks turns out to be hard as they usually just send a team of engineers round to the company in question to help out with the design.

You wouldn't believe the trouble we had getting the manuals for the DSP out of Philips. We had 500 chips for a couple of months before we got the databook...

We're working on AM/FM, and it will arrive.

Hugo