2.0T M8 trouble Gearbox/ Misfire

[Hillbeley]

Had a problem at 53000 miles, after pressing cruise resume from 50MPH, up to motroway speed !!, I had a major vibration, which set off the flashing engine management light and MFD showed 'gearbox malfunction you may continue driving with reduced functionality'. This meant only 2,3 & 4th and occasional minor vibrations. On restarting later the warning changed to 'gearbox malfunction you may continue driving'.
I booked an inspection for a few days later, but the chugging got worse and I limped in early morning for an inspection, the Audi dealer reported misfires on 1 & 3 and eventually burned plugs were replaced.
Now all better but possibly a minor vibration for the next service.
On reflection I had noticed a drop in MPG, and the smoothness had gone, so watch for these symptoms if you have a 2.0T (mine's an SE Avant with Multitronic).
Any other cases, any suggestions? I don't make my own petrol!

[Hillbeley]

Update to my misfire problems, since the first post I have recently had my 4th set of plugs at 70,000m after the EPC light came on and the car went to limp mode - 40MPH on the M5 is not funny, and I am getting to know the Audi Assist operators (who have been great btw) and the RAC lads very well.
The Audi dealer has failed to diagnose the root cause, and they have the car again this weekend.
Has no-one else had misfire problems? I heard this was a coil problem on earlier Audis but had been cured.

[Hillbeley]

I have had the car back after almost 4 weeks, the engine has been re-built under warrranty, with new pistons to modify the combustion chambers. The extreme oil consumption I have had almost from new and the many burnt out plugs were related.
As always, the car ain't the same, gone is the smooth drive train it now feels rough. Maybe the MPG will improve to compensate!
I spotted an Australian post with the same symptoms, so I think this could be repeated soon, mine was a high miler at 70K.