This information appeared in car mechanics mag (also good forum www.kelsey-forums.co.uk/cgi-bin/cmm/YaBB.pl)
Some vw cars have diagonistic enabled radios and it must be fitted for diag. socket pin 7 to supply the correct voltage +5V (can be checked between pins 7&4 or 7&5)
If an aftermarket radio has been fitted pin 7 will supply +12V !! possibly damaging the interface.? If no radio is fitted pin 7 will also supply the incorrect voltage.
I haven't got the July/Aug magazine to hand but I don't think that this was mentioned in the article. Or has the interface got it covered?
