2 year old superb with 29 k miles.at around 55/60 mph I,be been hearing a droning sound .got the two front wheel bearings changed then got the EGR valve changed.The noise is still there ,very annoying.Anyone any ideas what it could be ?Thanks
Difficult without actually hearing the noise but it sounds like it could be something loose vibrating - is there a sump guard? Many cars have them just to improve the air flow and it's surprising how often you can see them hanging loose.
Further to TWR's suggestion, is the noise road speed or engine speed related. In other words, if you change down a gear does the noise disappear or change note? If so, it's engine related. If not it's body or wheel related.
Rub your hand over the tyre tread on the rear if it feels smooth rubbing one way and has sharp edges rubbing the other then it's probably got sawtooth wear. Rotate the back tyres onto the front and see if that does anything.