Sounds like the pads aren't getting far enough from the discs after application. This usually happens after replacement where the pads are exactly flat and the disc has dished wear with a certain amount of lip.
Depending on what has been done the answer (to your problem) changes. New discs and pads will probably solve it. New pads of a softer compound will also probably do the trick.
Owner 24 bay BSC
Bosch Master, ASE master L1
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