I found that honing the (original) front discs cured high speed brake judder on my 70,000 mile Audi. Handbrake on, chock wheels, remove front wheel, start engine, engage D or first gear, apply Black and Decker fitted with carborundum wheel to rotating disc surface. Gets rid of any lipping as well as dealing with areas of unequal coefficient of friction which causes the judder.

I found that honing the (original) front discs cured high speed brake judder on my 70,000 mile Audi. Handbrake on, chock wheels, remove front wheel, start engine, engage D or first gear, apply Black and Decker fitted with carborundum wheel to rotating disc surface. Gets rid of any lipping as well as dealing with areas of unequal coefficient of friction which causes the judder.

But were you able to get to the inner face of the disc or was it only one side you did. When I fit new pads I always clean the discs with coa*** abrasive then use brake cleaner but only by rotating the disc by hand. Normally deal with any lip by chamfering the edge of the new pad slightly so it fits flat on the friction surface. Never had an issue after even though new pads on used discs do take a few days to bed in. Historically I have managed 2 sets of pads before the disc need replacing.

pleased you founnd the cause