Strange Tyre wear B5.5 130

[passat130PD]

Hey guys,

my tyres are wearing on both sides, the middle thread is fine has about 5mm left vs the inner and outer side are nearly bald! i thought under inflation at first but i have 35psi in the two fronts so if anything they are slightly over inflated, ball joints are fine, i did have a simlar issue before i got my rs6 rep alloys, when i had the standard 15" on they have a tendency to wear out on the inside my wheel alignment guy told me the camber was out and that on these cars there is no camber adjustment, but because its wearing both sides with the 18" alloys i thought it may be something else?

so what do you think guys? if it is camber is there a fix for it (apart from replacing the stub axle!?)