Have the same thump (normal mode, didn't try in sport/+...) when braking and took the shop foreman for drive. Said it was the transmission down shifting. Will update when I hear back from the service...
Had to take the car to the shop for PSM error that pops up during braking. I'm also having porsche check the soft / mushy brake feel along w/ odd noise the brake pedal makes during braking. PSM error disappear after vehicle restart but PSM error comes back after every drive w/ regen activated...