Aaaaaaaaaaaaaaaaand it all makes sense now...
When I bought the car there was a tape in the head unit, forgotten by the previous owner I thought. Well that is until I looked at it, labelled "Beethoven's Symphony Number 6", I thought it was a **** take. But there was also no tape in it...
So the only device I have to connect to the jack to test it is my girlfriends little digital dictator thing, tested it with the tape carcass and now I know I have a line in of sorts, even if it's not on a dedcated aux input. Hardly ideal though, a choice of music or sat nav.
The other thing I've thought of is a bluetooth connection. If I paired the sat nav with the Zeds phone bluetooth I wonder if it would output the voice via the phone system...? Any ideas folks?
Thanks,
D.