I have been told that the timing chain on my car needs to be changed. Thankfully it is being done under warranty. The emission light came on and they found that it was slipping a little. Have got it booked in a week on monday. Apparently its a massive job, whole gearbox needs to come out to get to it, 3 days work I have been told.
I have been car is safe to drive as long as chain is not noisy. Once the chain starts to rattle then you HAVE to change it asap. Was told to drive it with a light foot and no sudden acceleration, frustrating as the car is made for a heavy foot.
Guy at audi told me that it is very rare, the chain is supposed to last the lifetime of the car.
Good luck with it mate. But if any way you can afford it, I would get it done. If it goes then whole heap of trouble.