Weird vibrating/droning sound.

[Dacvolvo]

Hi, Folks

My Dad has a T reg 1.8i S40.

Whenever he applies the brakes, there's a loud droning/vibrating noise that seems to echo throughout the whole body of the car, but it's definitely coming from the front.

I though it might be a link arm or a rubber gromit somewhere. It only happens when he's braking gently from about 10-15mph. He can brake from 70mph all the way down till about 10mph and then it starts. As soon as the car stops completely, you can still hear the noise echoing through the chasis for a second or two. He's replaced the front 15" alloys and tyres (with a friends 17" versions) - no change and he's also had new discs & pads fitted - still no change at all...

It's really weird.

Any ideas?