E46 330 Disc warp through buckled alloy

[gazsharp]

Guys, has anyone heard of a buckled alloy warping discs. The alloy is fine whilst driving with no judder.

I am asking this as I am at the end of probabilities as to what is causing only one disc to warp giving steering judder after 2500 miles.

The car has seen 5 sets of discs in 15000 miles.