MMI doesn't remember anything
 

MMI does everything I tell it but when ignition is off for, say, 15 minutes it reverts back to factory settings. So German language, TP on, no saved radio stations, BOSE settings back to boring etc.

Is there some lithium battery that has failed or is there a memory prong that's burned out? I haven't upgraded software yet: will that help?

Advice welcome.

Have you had a VCDS scan yet? Might throw something up.

I know nothing about MMI or D3 electrics but I would have thought there should be a permanent live to the unit for setting retention and it sounds like this is missing. I would expect this to be through a low value fuse (3 amp) maybe on the unit itself?

I have seen a couple of threads on this elsewhere, several people with 2003 a8's both running firmware D3-HU 6300 02.9.0 0309. the suggestion was to update the software as a first step, but also a theory that a failing car battery could be at fault in some way

If you can get hold of the CDs, then go for an update, but always good to do a VCDS scan first to make sure it's all clear.

Got the CDs but the VCDS thing: I've found a download for a lite version but then where does it plug in and how do I use it?

You need to have the diagnostic cable and stuff too :)

Hopefully someone localish to you will be along soon that could scan the car for you.

I have a spare Gendan cable that'll work with the free downloaded software, i no longer use as i have a genuine cable now. You'll be quite limited to what can be done with it tho.

Is that a CAN-BUS cable Dezzy? If not, then it's almost useless in a D3 :(

No :o I'll get my coat