I phoned the VW garage that performed my last service and they confirmed that they would have checked my tyre pressure. I asked what pressure they inflate the GTI tyres to and they said 2.2bar, not the 2.4bar that is specified on the fuel filler cap.
I am gonna get the tracking checked at the weekend. In the meantime I have just had to replace the front tyres, so have got some assymetrics on the front now. Grip, ride and noise much improved.