I've been going to Pirelli's Agent workshop at Glenmarie for some time but lately I noticed their on-wheel balancing was always out. Everytime after the alignment and balancing (incl on-wheel balancing) were done, I still experienced vibration at steering wheel and the seat at abt 2700-2800rpm (120-130 kmh). At higher speed they were gone.when I was using Continental tyres I have the same issue. After changing to Pirelli's tyres experiencing the same issue but lesser vibrations but they are still there.Can somebody help this out? Could it be the active steering issue or pure inefficient service provided? By the way I'm driving E60.Would appreciate if somebody could suggest a good workshop to go to. I heard Sunny at SS2 was good. Have tried calling him but nobody picked up.