sounds bad. the only way i think it would be a tyre issue would be if one was very badly flatspotted. however, if after ortating the wheels and tyres and the noise is still there, it sounds mechanical.
also, dont be so sure about ford not allowing a car to be sold with noisy tyres. had a mondeo that was unbelievable at anything above 80kay, or 60 with people in the back. new tyres gave no noise at all. it was that bas that myself and a mate independently thought the rear wheel bearings were f*#ked.
big difference here thoough is that wheels gave a lot of press to th noisy tyres on the mondeo...nobody else has mentioned the problem you seem to be having.
good luck mate.
You wash your car like it was your firstborn child, you tend to its needs like it was your own body, you protect it like it's your family, then you drive it like you stole it.
Weapons of rice destruction
2002 Ford Falcon AU3 XR6
1985 Ford Sierra XR4i
1980 Ford Escort RS2000