Lane keeping...wouldn't that be a kick in the head? I don't know if you can turn off both the audible and wheel vibration alerts and still have the thing lane keep. If so, that could be a steath cause.
Overinflated tires could be the issue. A poster a while back reported wandering in his new CX-5. The vehicle was delivered with tire pressure at 40+. Letting the air out solved his problem. Surely by now the tire pressure has been checked. Or has it? Perhaps out of balance wheels? Worse things have come out of the factor.