Well now i've checked, double checked and then checked again for construction faults (things turning the wrong way around, solder shorts and so on) ... i've tried the antenna trick, no luck... i've checked that the pinheader connecting the two boards also works..

i've checked the powersupply on the board, no problem.

i've tried connecting the CPU board alone, and in fact it reacts just as when i've the two boards connected, is this normal?

now i'm kinda run out of ideas, ... it's a bit sad... i was planning on finally mounting my empeg when i got this tuner, but now i have no headunit at all in my car which is very annoying. HELP