Mike_F_Black Edition

Hi All, I have been running my A4 B8 Black Edition ex demo for 6 months or so, now a year old with 14K on the clock. I had recently noticed a notchy effect on the steering around the centred position. The car went to Audi and the outcome was a software update for the steering performed under warranty. Somehow the steering position sensor had lost centre. The car seems far better now, but the 19" rotars are giving horrendous tram lining, and the car constantly wants to change direction. I believe it is the Continentals, already well into the second set of fronts. Have filled with Nitrogen, but makes no real difference. Thinking of changing to Michellin next time. Has anybody else suffered tram-lining and what other brands of tyres work well to reduce it? Regards, Mike