Did you clean the hub before fitting the discs and is the centre bore exactly the same between hub and disc?
I chased similar symptoms for ages until I measured the center bore of hub and disc and realised i needed a really tiny spigot ring to stop the vibration.
The front hub and bearing unit are all brand new and i made extra sure there was no debris there. Used an aerosol copper grease on the mating surface to prevent seizing.
Pretty sure the discs located perfectly on the hub, in theory they are the same bore as any of the 312/340/345mm discs. I'll measure eveything accurately when i investigate over the next fortnight.
Are you sure it's the brakes? Did you change or fit anything else at the same time? Might be worth getting a cheap dial gauge off Amazon to confirm.
I have the same discs and been using them daily for 9 months. The humming noise went after the pads bedded in and they haven't warped. It's not unheard of for VAG discs to warp easily though, so you might be able to get replacements if they were fitted correctly.
If yours were also not L&R handed when you bought them, that is also a case for a refund/swap because it means one disc runs a lot hotter than the other. I think I got a pair of Rights. I did ask the dealer about it but VW only list one part number for both sides.
I fitted lots of stuff at the same time to be honest. Alloy hubs, bearings, lower arms, lower ball joint, track rod end, ARB. I have a decent dial guage at work so i'll have a play with that maybe. Do you think it would show up?
Mine aren't handed that's for sure, both drivers side in effect. Perhaps i should approach AKS for some advice
Thanks for the advice chaps.