I have this issue on my Touran. Mileage is about 29k; tyres on the rear are both Goodyear NCT 5s. Not sure how long they've been on the rear as I only bought the car in March and they could have been moved from the front previously. They are showing the sawtooth wear on the inner edge. The symptom is tyre noise at between 40 and 50mph. It seems less pronounced at higher speeds, but I'm sure it's not as quiet as it should be.

The advice I've had from a local tyre fitter is that it's a feature of this kind of car and may be due to running with little weight in the rear, in a car designed to take a considerable load. Looking at the amount of wear they reckon it's probably not worth spending £100+ on a full 4-wheel laser alignment as the wear would have been worse if alignment was out. TBH I wouldn't mind spending that if the alignment is out.

I'm replacing the rears with a pair of Conti Premium Contact 2s tomorrow. Looking forward to a bit of peace & quiet from the back, at least when the kiddies aren't on board!

The Touran is based on the Golf Mk V platform as I understand it. Do later Passats have the same independent rear suspension set-up?