In2 is actually "Inspection 2". It's a reminder that you should take the car to the periodic inspection.
This does not imply that you have problems with the car. When driving a certain amount of kilometers from the last inspection, this reminder flashes to let you know that you should go to a new scheduled inspection.
The garage usually resets this at each inspection. You can also reset it yourself with a vag-com, if it's annoying. However, this indicator has no effect on the car's behaviour, and is not a direct sign of any problem.