Prolly just wheel alignment, a simple check costing about £20 will highlight if its out, are your tyres fitted with the direction arrows pointing in the direction of travel (no idea if this would contribute to anything actually...but still they are on the tyres for a reason).
Just watch who you get to align your wheels as kwik fit muppets etc generally dont give a toss for your nice alloys and the alignment may damage your rims, so agree up front any damage with them before you let them loose.
Alternatively go for 4 wheel alignment somewhere using a VW beissbarth (will cost you about £150 ish).....
