Problem tonight - onboard computer crash?

Do you have a diesel...? Could it have been the DPF regenerating?

Diesel particulate filter, what you're experiencing with the SS and fans is totally normal for a regen. Nothing to worry about.

The MMI though will need Audi to investigate.

Agree with a6-chris though... sounds like 2 separate issues. Pretty sure its the DPF and nothing to worry about!

when you say "extraordinary amount of heat; to the point where if I had left it I would have been concerned for a fire." do you mean the temp gauge was higher than normal? or it just felt very hot on your skin?

cause wrt engine damage, i think you should judge by engine temp gauge.

Definitely the DPF, mine does the same. How it works is thus...

The DPF filters out the particulates so you don't belch smoke everywhere. After a while it will start to get clogged up and will need to be cleared out or "regenerated". This happens when the temperature of the DPF reaches a very high figure, circa 600C if memory serves. At this temperature the particulates that have built up in the DPF are literally burnt off, clearing it out.

Now if you do a decent long, reasonably high speed run regularly then this process will occur automatically as the exhaust gas will heat the DPF up to the required temperature. If you do mainly urban driving with short trips then this process will never get a chance to happen.

In this case, once the DPF unit needs clearing, the car will decide that it can no longer wait and will effectively force the issue by doing a "manual" regeneration cycle. The engine is run in such a way as to force the temperature of the exhaust gas up in order to make the DPF regenerate. This is the process you've noticed.

The tell-tale signs are the idle revs will be 1000rpm rather than the usual 800rpm and, as you said, an incredible amount of heat will be evident from under the car. If you stop and turn off the engine during such a cycle or just after one has completed, then the engine cooling fans will run at full speed for a while afterward simply because everything is so hot. Stop/start is also disabled whilst such a cycle is taking place.

If you continually interrupt this process by turning off the engine before it's had a chance to complete then it's possible the DPF will never get a chance to regenerate which will culminate in a warning on the dash to this effect. I've yet to see this in my 8V but had it a couple of times in my previous cars.

As for the computer issue with the music selection, that's just be the MMI having a bit of a fit - mine has crashed a few times. Just reboot it with the three-button press and you'll be fine.

Strangely, I haven't noticed mind regenerating for a few months! I'm on the motorway most days with the revs just under 2000 for at least 20 mins, so hopefully all ok. Not had any warning messages on the dash.