Thank you for the replies. I have been checking the Audi wiring diagrams and I am now almost sure there is a permanent +12v where the empeg wants a the ignition switched +12v. I'll get in the dash and sort that one and hopefully that will cure the power off thing. I have found the power off seconds function in JEmplore so I'll have a play with that too once I have the wiring sorted out.

My car didn't have the correct aerial when I got it so getting the right one is in my around to it list. To be honest the reception seems ok, so it is really a niggle more than a problem.

Thanks again