I can't say I recognize that sound.. However I had a "tooth" breaking clean off one of the gear wheels, which made a horrible sound driving in 1 - 2 - 4 - 5 - 7 - 8 - 10 and 11th gear
Luckily the bit that broke off, didn't make further damage, since it was sitting nicely on the magnet bit at the oil drain plug.
My gearbox is the 12 speed, second generation Opticruise.
From the sound of the video, I second the theory of a faulty bearing..